A group of detectives and officers work at the 15th Precinct, a seedy police station in Manhattan, New York City. Detective John Kelly, a 15-year veteran of the force, deals with his partner Andy Sipowitz, an alcoholic 20-year veteran detective. Laura Michaels, an aspiring lawyer and Detective Kelly's wife, is having problems with their marriage and she hires Josh Goldstein, a lawyer who lives in apartment 4B of their building to work on a divorce, who gets mugged in the laundry room of the building. Meanwhile, Sipowicz is relentlessly pursuing mobster Alfonse Giardella, who threatens Sipowicz to leave him alone. Later, Sipowicz is shot by Giardella during a tryst with a prostitute. Enraged, Kelly orders the precinct officers to hound Giardella and his ruthless employer; mafia kingpin Angelo Marino. The new patrol officer, Janice Licalsi, is attracted to Detective Kelly. But is she is revealed to be an informant for Marino who orders her to murder Kelly.

Kelly begins moonlighting as a security guard for Susan Wagner, a wealthy woman who's married to an abusive husband. But things take a turn when the husband is shot and killed, and Mrs. Wagner becomes a suspect. Meanwhile, Sipowicz is paired with the hard-nosed Detective Walker who arrests a man for a robbery and double-murder. While Detective Walker thinks he's guilty, Sipowicz thinks differently. Laura quits her job and plans to move into a position with the District Attorney's office, prosecuting narcotics. The increasingly edgy Josh Goldstein has Kelly appear at a tenant's readiness group regarding crime, and he is later killed trying to save an elderly woman from a mugging on a subway platform.

A minor skirmish on a basketball court leaves one of Kelly's friends dead and the other one in jail for manslaughter. Meanwhile, Sipowicz is convinced that a man knows more about his wife's death in a highway shooting than he is letting on. Laura feels as though she's being dangled in front of Giardella when Sylvia tells her to push on him harder. Janice saves Kelly's life during a drug raid and the event seems to bring them back together.

A shady homeless man, named Lou, comes to the station thinking he's a werewolf and demands to be locked up into a cell before he kills someone when the night comes. However, things take a turn when Kelly investigates Lou when he may be a witness in the murder of a nine-year-old immigrant boy. Meanwhile, Sipowicz is visited by his long-estranged son, Andy Sipowicz, Jr. with his fiancée, Patty Constance, an older woman who Sipowicz discovers that she has been cheating on Andy Jr. Elsewhere, Giardella is killed in his hotel room by a Mafia button man dressed as a window washer before he can testify to a grand jury against his superiors and Laura finds herself the only witness to the murder.

Kelly, Martinez, and the officers arrest Luis Hernandez, a baker, for a murder charge. But Detective Mike Roberts, as well as Detective Kelly, try to get him to confess to the robbery of four taxicabs so they can link him to the murder. Meanwhile, Sipowicz arrests a topless dancer for prostitution and she offers to help him get the owner of the bar who's laundering money for the mob. Laura questions Sylvia's ethics, who tries to protect her personal reputation and Sipowicz's verbal attacks on her. Also, Lt. Fancy and the rest of the squad welcomes the new administrative aide, a beautiful blond woman named Donna Abandando, whom the neurotic Detective Greg Medavoy finds irresistible.

Janice is contacted by Richie Catena, a mob button man and former associate of Marino. They want her to start doing favors for them again or they will expose her past activities with the late Marino. Janice agrees to co-operate with them without telling Kelly, but she tells Inspector Lastarza who tells her to go along with it. Meanwhile, Martinez is distraught when he learns that his brother has died from a drug overdose. But their father, Hector, wants to go out and kill the pusher who's responsible for his son's overdose. Also, Medavoy celebrates his 40th birthday and later musters enough courage to ask Donna out on a date to an ice skating rink.

As Christmas draws near, the zone commander, Haverill, starts to come down on Lt. Fancy about his work skills and Sipowicz later intervenes and threatens Haverill to lay off Fancy or he will reveal some incriminating evidence about him being a racist. Meanwhile, Kelly and Sipowicz investigate the kidnapping of a doctor's daughter. Janice must pass some more information to the mob about the station's moves and wonders how she will get out of this situation. Also, Martinez and Medavoy question a woman and her young son who claim to have been robbed by a man who picked them up while they were hitchhiking in North Carolina. But Martinez later discovers that the woman, Kathy, is not who she claims to be, which leads to a hostage situation, involving Donna, at the station. Sipowicz reluctantly plays Santa as the precinct's annual Christmas party, and Martinez receives his gift from Lt. Fancy when he is promoted to detective, while Medavoy panics when the station's pet cat eats the Christmas rabbit, and Kelly visits his Alzheimers-stricken mother who resides in a nursing home.

Medavoy leaves his wife and finally tells Donna about his romantic feelings for her, which turn out to be mutual. Sharon LaSalle, a police academy classmate of Kelly's, joins the squad and shortly after, she and Sipowicz investigate the death of her husband, Danny, who was an ex-cop trying to stop a robbery during her first day at the 15th precinct. Kelly and Sipowicz relentlessly try to track down the two robbers responsible, while an an ambitious publicity-seeking reporter plots to take advantage of the case to further advance his own career. Meanwhile, an alcoholic woman keeps lodging complaints to Kelly against her abusive husband that she never follows through with.

Sipowicz has a cavity and decides to have it taken care of by his son's dentist. At the dental office, Sipowitz finds himself unsuccessfully trying to prevent the suicidal Dr. Fleishman from jumping off a 28th floor ledge. Meanwhile, Medavoy and Martinez work on a strangulation murder case that appears to be the work of a cross-dresser. LaSalle's first case for the squad involves a woman who was raped and she, Kelly, Sipowicz try to catch the most probable suspect. Janice joins the undercover squad and is partnered with the hot-tempered Roy Larson to assist with LaSalle's case, while Sipowicz suspects that Larson's short temper and odd behavior points to a drug problem. Also, Lois Snyder (the prostitute who set Sipowicz to be shot in the premiere episode) returns to try to apologize to him about the incident and also wants to renew their romance. But Sipowicz turns her down and goes back to start whatever relationship she has with D.A. Sylvia Costas.

Lt. Fancy insists to a reluctant Larson that he take a drug test and when it comes back positive of methamphetamine use, he is fired. One of Detective Mike Roberts' informants/girlfriends comes to the precinct and causes trouble for him, especially when she later turns up dead, and Roberts becomes a suspect. Although Roberts ends up being cleared, his reputation is ruined and he decides to quit the police force. Meanwhile, Sylvia has trouble getting through to Sipowicz to give their relationship another try. Also, Laura appeals to Kelly to help her re-examine a case she is prosecuting of the alleged murder of an abusive man by his wife, in which Martinez and Medavoy investigate one witness and discover some conflicting facts in the case.

Medavoy suffers a stress-related anxiety attack while working and doesn't want to tell his wife about his personal problems, which displeases Donna who wants him to work things with his wife. Meanwhile, Sipowicz looks into the robbery of a wheelchair-bound Vietnam veteran, who later takes his muggers hostage. Elsewhere, Detective Kelly starts moonlighting as a bodyguard for Robin Wirkus, the young girlfriend of Jimmy Wexler, an ailing wealthy friend of Kelly, and Kelly later stumbles into a complex blackmail plot by an extortionist, named Stan, who asks Robin for sexual favors. Also, Laura tells Kelly that she have moved on with her life and is dating someone.

Mike Roberts meets with Kelly in search of getting some bodyguard and/or P.I. work for himself after quitting the police force. Meanwhile, Laura feels someone is stalking her and gets Kelly to meet her new boyfriend, Dr. Schrager, who may be the stalker. Elsewhere, Sipowitz and Kelly deal with a woman whose boyfriend was a material witness and is afraid to identify the hit man because he's afraid the hit man's friends will kill her next. None of the detectives are too excited when Haverill sends them down to Times Square for uniform detail at a parade.

After Robin's husband dies, she gets angry when his will seems to stipulate that Kelly should resume his duties as her bodyguard. Meanwhile, Sipowicz must clear his own son of a drug pushing charge. While investigating a tip on the location of a dead woman, Medavoy, Martinez and Kelly find another body of a dead man in a garbage dump which leads to Kelly suspecting a hotel concierge and the hotelier of conspiring to murder the hotelier's husband.

Janice is promoted from vice squad officer to detective and will be working with the other detectives until she can be transferred to the re-organizing intelligence division. Meanwhile, Kelly suspects that his friend, Charlie Lear, is being framed for the murder of his mistress, even after his erratic behavior in the squad room points to his guilt. Fancy's wife tells him that she's pregnant again and he is less enthusiastic considering the complications of her two previous pregnancies. Also, Sipowicz falls off the wagon when he starts drinking again at a birthday party for Sylvia's father.

Medavoy tells Donna that he's caught his wife being unfaithful yet again and decides to move out. But he crashes at the station since he cannot afford a place to live. So, Donna asks him to move in with her. Meanwhile, racial hostilities flare up in the community after Martinez shoots a belligerent black motorist who draws a gun on Medavoy, but the gun goes missing. Janice becomes more and more distressed by the recent events and after talking to Kelly's preacher friend, Father Downey, she confesses to Fancy that she was the one that killed Angelo Marino and his chauffeur. Also, Sipowicz tries to attend an open AA meeting with Sylvia's support.

Kelly gets an ultra-high priced mob attorney to defend Janice on the double murder charges and helps out with her bail. Meanwhile, Sipowicz tries to make amends with Sylvia who's been attending Alanon meetings. While helping with Andy Jr. look for a new car, Sipowicz comes across a lead in a disappearance case that has frustrated him for the last 2 1/2 years. An old Ford van which may have been used in an abduction re-surfaces at the lot. Elsewhere, Kelly investigates the murder of a priest and later meets with Robin for a lunch date and spends the night with her.

Janice's murder trial begins, where Kelly risks the consequences when he testifies on Janice's behalf about their brief affair which results in the Internal Affairs Bureau investigating him. Meanwhile, Sipowicz works with an abused woman who's reluctant to testify against her husband. Medavoy, Martinez, Sipowicz and Kelly investigate robberies of drug dealers in their apartments. Sipowicz's AA sponsor wants him to agree to abide by a contract before he lets him try to restart his relationship with Sylvia. Donna tries to give Medavoy advice about dealing with his divorce. Also, Robin leaves Kelly for good when he tells her that he still has feelings for Janice.

Internal Affairs begins to investigate Kelly and Sipowicz's arresting of the officers they caught robbing drug dealer's apartments, then they begin looking into Kelly's handling of the notebook that was part of Medavoy's case. Janice's murder trial continues where she takes the witness stand to give an emotional testimony about her reluctant involvement with the mob and is sent to prison with a two-year sentence. Meanwhile, Kelly and Sipowicz investigate a double murder.

Kelly works with a Chinese detective in the investigation of the murder of an off-duty cop in Chinatown. Lt. Fancy catches Donna and Madavoy in an embrace and warns both of them about relationships in the workplace. The abused woman Sipowicz helped out turns up dead and her husband is a suspect. Meanwhile, a tough new female detective, Adrianne Lesniak, transfers into the squad because of a relationship she had with an officer at her former precinct in the Bronx and begins to work with Sipowicz on his case.

Martinez investigates a baby that was killed in a car from an apparent drive-by shooting. Meanwhile, Lois Snyder contacts Sipowicz for help because a policeman that she was entertaining died in a compromising position and he moves the body to a less conspicuous location. Lesniak's ex-boyfriend, Officer Abruzzo, keeps showing up at the precinct and harassing her, while at the same time, Lesniak locks horns with the officious Vince Gotelli over his working skills and his racy items he keeps. Kelly's future with the department is decided when Internal Affairs comes to the precinct to re-investigate some of his old cases and the result is Haverill transferring Kelly to borough dispatch duty. But Kelly decides to quit the force and after saying goodbye to Sipowitz, he throws in his badge for good.

Bobby Simone, a widower and homing pigeon breeder, joins the squad as Kelly's replacement. Simone's first assignment is to help Sipowicz in the investigation of the hit on a mobster's son, where a stray bullet also hit an elderly woman in her apartment. Meanwhile, Lesniak tries to help a woman who's worried that her husband is molesting their daughter, and an over-the-edge Abruzzo pulls his gun and threatens Lesniak in the squad room for leaving him.

Simone and Sipowicz suspect a chiropractor of murdering his wife. A woman whom Simone knows finds her 11-year-old son in possession of a gun. Meanwhile, Medavoy tells Donna that he has changed to a high-fiber diet a part of yet another change in his life. While moonlighting as a security guard for Mike Roberts, Martinez becomes attracted to Leticia, a college student he's been assigned to protect and she's worried about her possessive father, a Colombian businessman who may have criminal connections.

Donna's younger sister, Dana, arrives and moves in with her and Medavoy, and tries to make the moves onto him. Simone doubts the confession of his friend's 11-year-old son, a murder suspect in a gang related shooting at a school. Meanwhile, an HIV-infected Lothario comes to the station and asks Lesniak and Martinez for help when he appears to be targeted by a woman he's apparently infected.

Sipowicz's AA sponsor, Danny Breen, is beaten up by his estranged son. Meanwhile, Simone and Sipowicz investigate the murder of a pregnant woman whose charred body leaves few clues. Martinez and Medavoy check out the story of a man who might have information about a pawn shop robbery.

Simone and Sipowicz investigate the murder of a gay bar owner during the Christmas holidays. Meanwhile, Fancy's wife goes into labor to have her baby. Breen breaks his promise to Sipowicz by checking up on his son and decides to go back to him, which turns out to be fatal when Breen's son kills him and Sipowicz has to arrest him.

Lesniak deals with a perpetrator and his "high priced lawyer and shrink" when he repeats the offense. Meanwhile, Detective Solomon uses a fast pull to take a possible serial killer case away from Simone after he brings in a possible suspect. One of Fancy's old contacts, Vinnie Greco, brings in a tip about a couple of guys looking for some heavy arms to do an armored car job and Sipowicz works with him, but Greco is working for someone else against Fancy. Sipowicz invites Andy Jr. over at his place for dinner where his son tells him that he is joining the Air Force. Also, Sipowicz proposes marriage to Sylvia and this time, she accepts.

After discovering a key piece of evidence, Simone gets his chance by Detective Archie Solomon to question the serial killer suspect George Putnam. Meanwhile, Sipowicz, Medavoy and others work on how to stop the armored car robbery and Fancy has a confrontation with Haverill about using his informant, Vinny, as a pawn to try to bring him down and plays a tape for Haverill which he reveals his true attitude which results in his resignation as the zone commander. Also, Martinez and Lesniak arrest an odd extortionist, while romantic feelings for each other begin to appear, and Simone also develops romantic feelings for his writer friend Benita Alden.

Simone and Sipowicz investigate the brutal murder of the teenage daughter of a woman whose ex-husband has made threats against her. Meanwhile, Lesniak and Martinez's latest case involves them trying to nab a con artist who sells a black box to homely women, promising them beautiful skin. The new zone commander, Captain Clifford Bass, checks in and lets Fancy know his overtime policy, which doesn't sit well with Sipowicz when it compounds their investigation. Elsewhere, while Simone's romance with Benita becomes more serious, he also deals with a childhood friend, named Ray, who is now involved with a nightclub that is frequented by wise guys and other criminals.

Sipowicz disagrees with Sylvia over their wedding arrangements, for he wants to travel to Maryland for a quick one, whereas Sylvia wants a traditional Greek Orthodox service. Shortly thereafter, Simone and Sipowicz investigate an execution-style murder of three people at a fast food restaurant and the investigation leads them to travel upstate to look for a possible suspect. While there, Simone tests his homing pigeons by releasing them, hoping they will make it back to New York. Meanwhile, Lesniak meets an old high school boyfriend of hers, now a doctor, while investigating a rape case with Martinez, who develops a case of jealousy.

Sipowicz investigates the murder of a pimp in which evidence points to a cop that Sipowicz once helped out with a problem of his. Later, Simone mentions the case to his girlfriend reporter Benita, and soon regrets it when the story hits the papers which leads to the suspect committing suicide. Benita denies leaking the story, but Simone refuses to believe her and ends their romance. Meanwhile, Donna's former boyfriend, Harold, a ex-New York Ranger hockey player, returns to the city and meets with Donna, while Meadvoy overreacts with jealousy. Donna confides her situation with her sister, Dana, but she manipulates Donna by sowing seeds of anxiety into her about Medavoy and his neurosis. Elsewhere, Martinez begins to develop feelings for Lesniak.

Simone and Sipowicz collide in their squad car with a Romanian immigrant who has a woman locked in the trunk of his car and later, their investigation shows him to be a possible terrorist and holding a wealthy family prisoner with pipe bombs. Meanwhile, the serial killer, George Putnam is shot by an unknown sniper. Simone begins to investigate the father of the killer's last victim, Mr. Rudman, and another member of a victim's support group... who all appear to be part of a secret vigilante group. Medavoy talks to Dana about his relationship with Donna if he's losing interest in her, but the crafty Dana takes advantage of the situation to try to break them up by playing on his mental neurosis as the cause of Donna's lack of trust in Medavoy. Also, Martinez keeps asking Lesniak to go out on a date with him.

Simone and Sipowicz investigate the race-related murder of a Puerto Rican teenager who was attacked while spray painting graffiti in Little Italy. Meanwhile, Medavoy meets Donna's former boyfriend, Harold, when he comes to the station to file a car vandalism report, while Donna makes a tough decision about her relationship with Medavoy. Also, Sylvia is mugged and she later tells Sipowicz a secret from her past about being raped as a teen.

Simone deals with an emotionally fragile woman, named Joyce Novak, whom is a witness for a double-murder when she keeps changing her story, for she is really only interested in flirting with him. Meanwhile, Sipowicz participates in the investigation where a family-run business, that he used to work in, is held up and the owner's wife is killed. After Donna leaves town for a long vacation (and to get away from the annoying Medavoy), her temporary replacement, John Irvin, is a flamboyantly gay man whom Simone used to know from his old precinct. But Irvin makes the whole the station, including the bigoted Sipowitz, uncomfortable. Also, Martinez enters in a police department boxing tournament.

Simone and Sipowicz search for a killer following a shooting spree, which left several people dead and where a rookie cop's missed shot also killed a bystander. Meanwhile, Fancy's younger brother, Reginald, a policeman in the 8th precinct, has racial troubles with his commanding officer and Fancy intercedes on his behalf and his own boss, Captain Bass, covers for him. Sipowicz sees a doctor and discovers he has an enlarged prostate and Sylvia mistakenly thinks their lack of sexual activity over the past few weeks was because of the rape incident from her past that she told him about.

Fancy works with Martinez to help him get ready for the inter-precinct boxing tournament. Meanwhile, Simone is attracted to the new undercover cop, Diane Russell, who is working with him to catch a wanted arsonist in a sting in which Lt. Fancy's informant, Vinny Greco, returns to offer more advice and annoyance to everyone. Elsewhere, a woman that Sipowicz gets to testify in a case is murdered by the men she was going to testify against, and Sipowicz tries to prevent the murdered woman's husband from going after the gang members responsible.

Simone and Sipowicz search for a killer of a bookie in which Mike Roberts returns to offer his help. Meanwhile, Donna returns from her long vacation trip to resume her position at the station and her temp, John Irvin, gives everyone farewell greeting cards when he is moved to the anti-crime lab upstairs. But Donna continues to treat Medavoy with resentment which leads to him thinking that she might be finished with him. Simone's obsessive witness, Joyce Novak, goes too far when Simone rejects her advances after he tells her that she will not testify in the upcoming trial. This leads to Joyce attempting to murder Diane Russell when she correctly assumes that she and Simone are romantically involved. Sipowicz and Sylvia meet with the priest to help with their wedding and later she hears a story about what has contributed to Sipowicz's loss of faith.

A witness to a crime smells alcohol on Russell's breath and uses it against her, and Sipowicz smells the same. Simone then confronts Russell about her drinking, but she tells him to mind his own business. John Irwin comes to Fancy for help when he and his gay lover are beaten up by gay-bashing officers in another precinct. Meanwhile, a terminally ill infant helps the detectives locate a serial rapist. Medavoy meets with his ex-wife who tells him that they should get back together for their kids and when Donna finds out, she tells him that their relationship is over.

Pre-wedding jitters put Sipowicz in a rare form of panic whereas Sylvia remains perfectly calm. While investigating a murder in Chinatown, Russell's drinking problem makes her miss getting a gun off a suspect and she finally admits to Simone about her alcoholism. Meanwhile, Fancy's brother, Reginald, is still having problems with his racist sergeant and his belligerent attitude has resulted in him being investigated by Internal Affairs. So Fancy, Simone, and the squad work together to help clear Reginald of any misconduct. Martinez finally goes out on a date with Lesniak and asks her to be his date for the wedding. At the ceremony, Simone is Sipowicz's best man, Sylvia's father escorts her down the aisle and even Andy Jr. makes it just in time for the ceremony. Medavoy brings his ex-wife to the wedding while a lonely and jealous Donna painfully watches from afar.

Martinez is shot in the back during a scuffle and the doctor's report is possible that he may be paralyzed for life. But Martinez's assailant, a government witness in a relocation program, will probably go free and Simone contacts reporter Benita Alden, his former girlfriend, to help put pressure on the D.A. to prosecute their protected witness. Meanwhile, Russell, on the road to recovery from her alcoholism, wants Sipowicz to let Simone know she's doing okay but she is on the brink of falling off the wagon. Donna expresses to Simone that she has feelings for him, and Sylvia tells Sipowicz that she may be pregnant.

Medavoy and Sipowicz go undercover as Hasidic Jews to recover a stolen Torah. Meanwhile, Simone gets a case where a father suspects his intellectually disabled son of killing his daughter. Detective Stuart Morrissey tactics with the suspect does not sit well with Lt. Fancy, despite the facts that the case match the one Simone are working on. Also, Sylvia visits a doctor who confirms that she's pregnant, and Lesniak keeps checking up on Martinez still in the hospital.

Meadavoy and Lesniak pair up to identify who's launched a series of vicious attacks on a man. Meanwhile, Simone tries to locate a possible suspect in a series of rapes. Russell tries to maintain her sobriety and it's strongly tested when her parents domestic problems get out of hand. Also, Martinez finally gets out of the hospital and returns to duty. But in a final surprising twist, Lesniak tells Martinez that she likes him as friend only... because she happens to be gay.

Lesniak's preference of her lesbianism quickly gets around the precinct, which gives her mixed reactions. Meanwhile, Sipowicz clashes with Simone throughout their investigation of the senseless murder of two kids, which is only the start of a really bad day which also includes Sipowicz dealing with Sylvia's morning sickness, and Simone dealing with Russell who falls off the wagon.

Fancy is less than enthused when Ronnie Drucker, a detective under surveillance by Internal Affairs, is assigned to the squad and Simone is asked to keep an eye on him. Both Drucker and Simone work on a case where an elderly man has been accused of exposing himself to a young boy. Sipowicz, Martinez, and Russell investigate the murder of a pimp in a laundromat which is witnessed by a young homeless woman who turns out to be Holly, the teenage runaway who helped the detectives out on a previous case (from 'The Bank Dick' episode). Meanwhile, John Irvin asks Sipowicz if he should approach Lesniak to congratulate her on "coming out." But she won't listen to his gay pride talk as does everyone else.

An Indian woman is found dead in a car and Sipowicz is full of theories about who killed her and why. While Donna is away at a computer camp taking courses for the week, her temp is a feisty middle-aged woman, named Evelyn, who has bad attitude and who clashes with Sipowicz and others in the squad as well. Meanwhile, Martinez and Medavoy are nearby when a drug crazed man, named Marv, tries to rob a couple of stores of credit card slips. Russell and Lesniak work on another case involving a man who was left to die of a drug overdose that leads to a chance of mending the feud between them.

Sipowicz becomes annoyed when federal agents take over their investigation of the disappearance of a millionaire. Then a petty criminal from the past surfaces with information about the kidnapping and Sipowicz decides to act on it. Meanwhile, Simone aids an old boxer friend of his, who happened to got him started with bird breeding.

Simone and the men from Internal Affairs share the suspect after Simone gets some information from his incarcerated friend, Ray, about a case that Mike Roberts once worked on. Meanwhile, Fancy and Sipowicz both work on the case of a self-confessed gunman in a neighborhood shooting, once they get the story they help the shooter out. Medavoy investigates the assault case of an actor who was injured in a staged fight that went awry.

Medavoy and his wife, Marie, split up once again and she comes down to the station to have some hard words with Donna, while he decides to crash there since he cannot afford a place to live. Meanwhile, Simone and Sipowicz team up with Detective Harold Ng to probe the death of a Chinese girl whose leg has a strange marking on it which may have been self inflicted. Martinez and Lesniak look into the robbery case where a woman in a wheelchair lets a man claiming to be a policeman into her apartment, while the husband reveals a clue to Martinez that he has been seeing a prostitute on a regular basis and whose pimp might have planned the robbery. Elsewhere, Sipowicz does not want to accompany Sylvia to her latest doctor's visit, and Martinez gets an opportunity to find out where Lesniak really stands on her sexuality if she's really gay.

Sipowicz has race relation problems with the organizer of a local basketball game, held in the memory of a young boy, which erupted into violence by the gang members on the opposing sides which left two dead and seven wounded, and was witnessed by a reporter. Fancy has problems when Sipowicz racist colors come to light and has him removed from the case, much to his anger.

Simone and Sipowicz look into the death of a young woman whose body is found burned beyond recognition, except for a tattoo on her back. Detective Vince Gotelli arrives from another precinct to assist Simone and Sipowicz with their case and puts his two cents in, much to Sipowicz's delight and one of the victim's roommates becomes the prime suspect. Meanwhile, Medavoy pulls double shifts for himself (to get away from problems at home) and is assigned to watch an informant who has a penchant for playing poker with his friends.

A strange woman walks into the precinct and gives Sipowicz and Medavoy some information about a disappearance that occurred eight years ago and where the body may be located. Meanwhile, domestic violence in Russell's parents apartment leads to tragedy when her drunken father is found murdered in their apartment and her brother, Doug, claims to have shot him in self defense. But Simone thinks otherwise and presses to get the truth about what really happened to her Russell's father and soon learns that Russell's simpleton mother in fact did the deed and Doug is trying to take the rap out of blind loyalty to the family.

Russell worries about her mother's pending grand jury trial for the intentional murder of her father. Meanwhile, Sipowicz and Simone search for the killer of a mobster's son, that reveals a family affair. The pompous lawyer of a suspect in another murder case impedes Medavoy and Russell's investigation and the erratic behavior of son of the victim doesn't help much either. Also, Martinez and Lesniak investigate another murder case that may be connected to Sipowicz and Simone's murder suspect who now may be on a killing rampage.

Donna and Simone give Lesniak and Martinez advice, respectively, on their plans for their first date and night together. Afterward, Simone and Sipowicz investigate the death of a young woman who was brutally murdered in her apartment and Simone and Martinez travel to Atlantic City to apprehend their suspect. Meanwhile, Medavoy and Russell try to find the perps who shot a wealthy and shallow surgeon during a mugging, and they also deal with surgeon's petulant wife who wants to press charges against her husband's mistress when she learns that she was in his company during the robbery.

Simone and Sipowicz get another murder case where a mild mannered professor is found decapitated in his apartment. Meanwhile, Martinez is helping out a former porno actress who is getting harassing phone calls, but Lesniak is not comfortable with the situation. Andy Jr. arrives in town with some news for Sipowicz, but he can't find the time to tell his father and finally at dinner, he explains that he has just been discharged from the Air Force and is joining the police department in Hackensack, New Jersey.

A detective from another precinct, Martina Escobar, joins Simone and Sipowicz with their investigation of a rapist/murderer who is throwing small children from the tops of buildings. Meanwhile, Martinez and Russell investigate an alleged case of date rape, but the women of the squad and Sylvia have a major disagreement with Martinez's decisions regarding the suspect. Elsewhere, Sipowicz shows his son the ropes of being a cop.

Simone makes contact with Ferdinand Hollie, an old informant, who wants to help him capture a pair of Colombian drug dealers who killed a young girl with their crossfire. But Hollie, a drug addict who is HIV-positive, has his own agenda to rob the Colombians. Meanwhile, Russell is paired with Sgt. Ray Kahlins, a "blowhard" from the federal anti-drug unit who is more interested in collecting overtime pay than catching a separate pair of drug dealers during a stake out. But Kahlins' brash tactics and disrespect for Simone and his informant Hollie, put both cases at risk. Also, Medavoy and Martinez investigate the murder of a Santería priest found in a local sewer and try to link a parole officer and a recent parolee to the crime.

Simone and Sipowicz help a local FBI agent, named Mike Frances, to investigate the murder of a local Italian mobster. However they are forced to commit robbery while working undercover for Agent Francis, and have to place a bug in the mob hangout. When two wise guys come to the station to file a robbery complaint, Russell and Medavoy catch them in the act of filing a false report. Meanwhile, Donna's hairdresser, Marina, tells her that she has a problem with her ex-boyfriend. He wants to hijack Marina's current boyfriend's truck, and Martinez goes undercover as Marina's boyfriend. But Lesniak is unable to hide her jealousy and possessiveness. Elsewhere, Andy Jr. learns more about being a beat cop with more pointers from his father Sipowicz Sr.

Sylvia is now nine months pregnant and ready to give birth any day so Sipowicz is on the edge. Meanwhile, Simone and Sipowicz, with Andy Jr. along for the ride, investigate a case where the drug-addicted nephew of the victim of a robbery-homicide is found holding the stolen goods. Meanwhile, Medavoy, Martinez, Lesniak, and Russell all join forces to work on the robbery-murder of a bouncer where the leads first lead to a biker, then to a check cashing forger, and to his co-worker. In the mist of the investigation, Martinez and Lesniak finally reach an agreement that they are not right for each other and quietly break up by agreeing to try a platonic relationship. Also, Donna contemplates an administrative job offer in California.

Just days after Sylvia gives birth to a baby boy (Theo), Sipowicz suffers an emotional setback when Andy Jr. is found murdered in the line of duty. Sipowicz wants Simone to lead the case of his son's killer and also wants the opportunity for restitution. With Russell in tow, Simone tries to balance his desire for revenge, as well as his quest for justice to catch the killers. While Sipowicz breaks the news of his son's death to his first wife, Katie, he begins to show signs of an emotional breakdown. In the midst of all this turmoil, Donna makes her decision when she quits her job as administrative assistant to the precinct and moves to California, leaving New York for good.

Sylvia confronts Sipowicz about her suspicions that he is going to late-night bars and drinking again, and the effect is everywhere. Lt. Fancy is forced to sent him home after Sipowicz walks in one morning drunk. Sipowicz even fights with some street punks, gets beaten up, and Simone offers to look for the men that beat Sipowicz up. Meanwhile, a new administrative assistant, named Lucy, arrives as Donna's replacement. Also, Russell investigates a young woman, named Angela, who claims to have been stabbed by her jealous boyfriend. Simone, following a lead from a streetwalker named Deena, finally tracks down and confronts the two thugs who murdered Andy Jr. and guns them both down in a hail of bullets.

Sipowicz meets with a priest to talk about his troubles and finally sees the light. Afterwards, he, Simone, and Russell work together to investigate a robbery where an auto mechanic got shot to death. Following the apprehension of a wounded suspect, the detectives also arrest the suspect's younger brother who is unwilling to make a statement against his brother out of blind loyalty. Meanwhile, Medavoy works on finding a new place to live while he, Martinez and Lesniak work on finding the suspect of a drug-related double murder. John Irvin passes out farewell notices to the employees when he announces that he is moving back to the 1st Precinct uptown. Simone and Russell plan a trip to the beach. Medavoy meets Anne McGuire, a new detective, while working on his case. Elsewhere, Lucy is disruptive at work and Fancy tries to find a way to transfer her out of the building. Baby Theo gets baptized which seems to bring Sipowitz and Sylvia back together.

Medavoy decides to go on a diet and has a hard time getting started on it. Meanwhile, Sipowicz has problems with his work, his baby son's illness and Sylvia deciding to return to work at the D.A.'s office. Simone proposes marriage to Russell, but she is hesitant to give him an answer. Martinez has eyes for Gina Colon the new administrative aide for the anti-crime unit since Lesniak has been transferred from the squad to another precinct, thus leaving the 15th for good. But none of the men are turned on by Donna's latest replacement, a frumpy lady named Gerri Turner as the PAA for the squad but she has a strong interest in Sipowicz. A body in a trunk of a car is inadvertently moved from the nearby 13th precinct into the 15th's jurisdiction. Elsewhere, Simone inherits an apartment building from a recently deceased woman and the woman's son, Henry, is upset at the situation.

Medavoy starts a bet with Sipowicz to see who can lose the most weight in a single month. Afterwards, Sipowicz and Simone help out Detective Stuart Morrissey on his investigation in the case of a missing baby. Meanwhile, Martinez campaigns to become the elected delegate for the squad and his opponent, Detective Vince Gotelli, is determined to win the seat himself. Also, Simone makes a deal with Henry to let him share ownership of the building.

An ex-con that Sipowicz put away a year ago approaches him and tells him about a prisoner who's been serving time for a crime he didn't commit and he and Simone decide to reopen the case. Meanwhile, Martinez wins the election by just three votes, much to Gotelli's chagrin. Simone comes across Detective Nick Savino who helps him with the investigation of the murder in his building and Savino suspects Henry has something to do with it. Fancy gets a cavity filling which makes him more edgy than usual and Medavoy loses one pound more than Sipowicz. Also, Russell still has not come to any conclusion about her relationship with Simone.

An African-American community activist, named Kwasi, with whom Sipowicz had a previous run-in, is found murdered in a drive-by shooting. Simone and Sipowicz investigate, and Sipowicz rekindles Fancy's and Kwasi's family's anger over the previous incident. Meanwhile, Martinez and Medavoy investigate a homicide at a bodega and have a hard time getting witnesses to cooperate.

A foreign prince and princess are assaulted - the princess goes into a coma. Sipowicz and Simone investigate, with Mike Roberts help, who provides them with some information about Prince Foresmann's contacts over some stolen artwork. Meanwhile, Martinez's first delegate situation gets a resolution that keeps Officer Ortiz out of trouble with the department. This doesn't work out as planned when two women claiming to be his wife are arrested in a scuffle. Russell begins a new undercover job that involves her getting into a relationship with alleged drug dealer, Jimmy Liery, that might require her to start drinking again. Elsewhere, Geri continues to try to win Sipowicz's affections and Medavoy for once feels good about himself after his diet. Also, Martinez asks the anti-crime PAA, Gina Colon, out on a date.

Simone and Sipowicz look into the death of a limo driver and try to find his last clients which included a gay businessman trying to cover up his secret cruising lifestyle. At the same time, Sipowicz finally lodges a complaint against Geri that gets her moved up to the crime lab area, while Gina is transferred down to the squad floor. Meanwhile, a new detective, Jill Kirkendall, joins the squad. Her first case involves investigating a man whose life is being threatened and this leads Kirkendall to suspect that the man's assailant's girlfriend has a stolen infant. Simone gets the approval from Detective Savino to question Henry about the apartment shooting and finally gets the real story. Also, Russell can't figure out how to talk to Simone about her current assignment.

Simone and Sipowicz investigate a claim of sexual assault against a mentally disabled 17-year-old schoolgirl, after her domineering and verbally abusive mother reports it. They try to persuade her to press charges against the two assailants. The alleged assailants are from privileged backgrounds who attend an exclusive prep school. One is the son of sleazy councilman Paul Manos, with whom the detectives had problems a year earlier. Meanwhile, a young man who speaks only gibberish, known to Sipowicz who had him committed four years ago, appears at the station and causes a minor scene -- trying to get someone to listen to him about a problem he now has. Sipowicz investigates. Meanwhile, Russell continues her undercover work and relationship with Jimmy, who shows off his true psychopathology when he beats up a roller blader who had accidentally bumped into Russell.

Simone and Sipowicz investigate a case where two transvestites witnessed a murder that they say was committed by a 'gay-basher' who's supposed to have been in jail for a previous crime. Meanwhile, Fancy's former foster son is arrested and charged with possession of a kilogram of heroin. He tries to make a deal with Sgt. Ray Kahlins, the "blow hard" from the DEA who worked out of the squad room the previous year, to nab the drug dealers. Medavoy finally asks out Abby Sullivan, the beat cop from the anti-crime unit upstairs. But she turns him down by revealing that she is a lesbian. Elsewhere, Russell gets more deeper involved in her undercover work which puts a strain on her relationship with Simone. But the psycho Jimmy's malevolence puts Russell's life in danger when he puts a drug in her drink.

While tracking down Jimmy, who drugged and date-raped her the previous night, Russell works with Martinez and Medavoy on a case where a man with a muscular dystrophy was killed in a very tight knit community. Meanwhile, Simone and Sipowicz work on another murder case that may have been masterminded by a married couple. Also, Fancy wrestles with Captain Bass and knowledge of the fact that Simone is going to be promoted to Detective 1st Grade, and Sipowicz isn't.

A woman comes into the station to report that there's a bullet hole in her wall. The gun is found in Jimmy Liery's apartment and Simone arrests Jimmy, but has to let him go as there isn't enough evidence to hold him. Simone finds out that Russell unsuccessfully attempted to scare Jimmy by firing a shot over his head. Simone decides to remove Jimmy unlawfully by setting him up to take a fall. Meanwhile, Sipowicz is still angry at Fancy who thinks he held up his promotion. Following a tip from a young runaway teenage boy, named Marco, Medavoy and Martinez investigate the murder of an apartment building tenant. Also, artist Walter Hoyt (from ep. UnAmerican Graffiti) returns and wants the detectives help to get his paintings returned from some mob guys that he is a witness against.

Simone and Sipowicz investigate a story that a diamond dealer and his partner report that one of the dealer's sisters is missing with a bag of diamonds worth a million dollars, but the sister's boyfriend is actually responsible. Meanwhile, Martinez, Medavoy and Russell look for the assailant of Gina who badly slashed her face up while she was on her way to work, and Martinez cannot cope with this sudden turn of events. Simone and Kirkendall go out on their first date, while Russell cannot cope with the fact of being alone again.

Simone and Sipowicz investigate a murder, but the procedures they must follow make them unpopular at the precinct when a fellow cop might have been involved. Meanwhile, Medavoy and Kirkendall investigate the murder of a young girl where the only clue is a videotape that starred her crushing worms. Russell goes missing and eventually turns up in Simone's apartment where she recalls to him that her father molested her as a child.

Simone, Sipowicz, Medavoy and Martinez together conduct an investigation into the death of a worker at a construction site, where more than a building is being framed and try to sort out a feud between two different unions. Meanwhile, Geri reports to Sipowicz about finding a friend of hers who has hung himself and Fancy suggests that Russell and Kirkendall conduct the investigation, which reveals the man died from kinky sex... with Geri. But the dangerously disturbed, sex-obsessed Geri will not speak to anyone about the case except for Sipowicz whom she has an obsessive crush on. Martinez stays close to Gina while she is recovering and preparing to get her stitches from her horribly scared face removed and offers him to let her stay the night with him.

Simone and Sipowicz investigate the murder of a woman whose body was found naked in the trunk of a car in a junk yard which leads them to a pervert with a penchant for lookalike porn actresses. Meanwhile, Martinez and Medavoy investigate a man who was found dead with a severe blow to his head from a typewriter. Simone hires Henry to take care of a painting job in the tenement building, where Henry comes in complaining about a difficult tenant. The emotionally and physically scarred Gina returns to work (with a large vertical scar across her left face), and Russell is working through her issues with her family problems by meeting a counselor.

Fancy and his wife are pulled over and harassed by a racist police officer for a burned out taillight, and he and the precinct commander, Captain Bass, don't see eye to eye on the procedures followed during the stop. Meanwhile, Sipowicz has some unresolved issues to work out Andy Jr.'s death when he begins having a string of dreams involving his late son. At the same time, Sipowicz works with Simone on a rare night duty and gets a case involving trying to find the perpetrators of a bar robbery, while Simone locks horns with the conniving Detective Eddie Hazell who is seeking to derail Simone's investigation to take the credit for nabbing the robbers all by himself. Also, Medavoy, Martinez and Russell work together on a sting operation to catch two female con artist investors defrauding old and crippled women.

Sipowicz and Simone investigate the murder of a woman whose body was found dumped in an alley and information about the mystery woman reveals that the woman was a mail-order bride from Russia who was looking to divorce her husband. Meanwhile, Medavoy and Martinez look into the drive-by shooting on a city bus. When one of the passengers mouths off his hatred of gays, both Medavoy and Abby become angry in which Medavoy slides on a further decline when he breaks his diet and begins to show off aggressive methods against the smart-mouthed gang members they bring in for interrogation. Elsewhere, Sipowicz starts working a part-time job for the U.S. Marshall by doing garbage detail at J.F.K. airport.

Simone and Sipowicz investigate a shooting that is related to the victim trying to leave a street gang. Meanwhile, Kirkendall and Russell investigate the death of a baby who appears to have been shaken to death by the baby-sitter. Medavoy and Martinez look into a murder at a garage where they have a suspect who looks guilty despite the fact he claims to have an alibi. That evening, Medavoy has dinner with Abby and her lover, Kathy. Also, Simone takes Russell out to a movie and proposes to her again, and this time she accepts.

Two trans women, named Angela and Peaches who assisted Russell on a previous case, arrive at the precinct where 'Angela' is seeking protection from a man who's beaten him. But afterwords, Angela is founded murdered and Sipowicz, Simone and Russell investigate. They eventually receive help from Simone's former junkie informant, Arthur Cartwell, to find the perp. Meanwhile, Kirkendell investigates the theft of some small items by a old friend's parents. Kirkendell confronts her old school friend, Lucy Hastings, to persuade her to return the items as well as enroll in a substance abuse program. Elsewhere, Fancy's wife, Lillian, tries to sell some health food products at the precinct, but Fancy begins to think that it is not a good idea.

Simone and Sipowicz get another case involving the shooting of a rap artist who refuses to cooperate with them in the identification of his assailant. Meanwhile, Abby tells Medavoy that she and Kathy are trying to start a family and asks him to donate his sperm to her so Abby will get pregnant. Officer Szymanski, the racist cop who pulled over Fancy, tells him that he thinks Fancy was one of the ones responsible for his being set-up and caught in the alleged theft of a drug dealer's money. Also, Simone is approached and propositioned by FBI agents to help them with their ongoing investigation into the affairs of mobster Joey Salvo. Elsewhere, the night shift detective, Vince Gotelli, tells Simone and Sipowicz about a heart medical condition of his.

Five Ecuadorians are found murdered at a small nightclub in an apparent robbery gone bad. Sipowicz, Simone, and Martinez work on the case where a tip from a waiter at the club leads them to try to find the two killers responsible. Meanwhile, Simone begins his undercover work for the FBI when he secretly meets with Joey Salvo who wants Simone to run a license plate number for him. Also, Russell and Medavoy are looking into a suspect in a spouse abuse case where Medavoy's commitment to Abby and Kathy hampers the investigation due to Medavoy's emotional attitude. Also, Medavoy discovers that Detective Gotelli is stealing money out of his locker in the light of his medical condition.

An inebriated Vince Gotelli is arrested after "hijacking" a city bus and having it wrecked. Fancy meets with the bus driver's boss to work out an arrangement about their investigation and suggests that Gotelli take some medical treatment. But it takes a forced intervention by Martinez, Medavoy, and Russell to convince Gotelli to get medical and psychiatric help in which Gotelli decides to throw in his badge for good. Meanwhile, Simone's continuing help with the FBI makes his life miserable when the men from Internal Affairs investigate him for the government license plate number on Salvo's car that he ran and is frustrated when he cannot tell them, not even Sipowicz, about what he's doing. Elsewhere, Sipowicz and Simone investigate the beating and murder of a woman in her apartment and deal with the emotionally sensate superintendent of the building whom they think he knows more than he's telling them.

Simone's continued involvement with the FBI sting against Joey Salvo jeopardizes his career when the men from Internal Affairs investigate him and suspend him from active duty. Meanwhile, Sipowicz and Russell investigate the gruesome murder of a young woman where a psychiatrist, named Dr. Wentzel, insists on implicating his patient's father for her murder. Martinez and Medavoy have a hard time over a haughty mugging victim who is a writer from a local magazine that wrote a bad story on the cops of New York City. Simone's involvement with the FBI reaches a cliff-hanging climax when in a secret meeting with Salvo, the mobster is hit by gunfire by an unseen assassin. Sipowitz, following Simone, comes on the scene and sees Simone standing over Salvo's dead body... and thinks Simone killed him!

In the four months since Joey Salvo's assassination, Simone is working odd jobs since he has been suspended by Internal Affairs pending their investigation, while he approaches Sipowicz asking about his and others incitements by the FBI who think that Salvo's death was an inside job within IAB, and Lt. Shannon from IAB tells Lt. Fancy that he may know the person who killed Salvo. Meanwhile, Gina discovers herself to be pregnant, but is hesitant on telling Martinez.

Simone and Russell investigate two stickups held at ATM's where they get a line on a possible suspect and then use Kirkendall to appeal to the suspect's mother to help them reach out to him. Meanwhile, Medavoy attempts to sort out a case where he can't determine if there really is a twin when a man comes to the station to report that his twin brother, Pete, has threatened violence against his former girlfriend. Also, Sipowicz contends with a medical problem involving his prostate while helping Simone and Russell and he is less than forthcoming with what his doctor has told him about his condition. Also, a new administrative aide, named Delores Mayo, comes to work at the 15th Precient as Naomi's replacement.

Richardson confronts Sipowicz and Simone about their impending questioning of his wife over the murder of the nurse, but with the exception that Richardson is a real bad person, Sipowicz and Simone reach nothing. In a cross-over from the series "Upstairs", former temp and private detective John Irvin stops by the station to tell the detectives about the new graphics art business he started. But with the exception of the receptionist Dolores, no one is around, including Medavoy who leaves in a hurry for upstate New York where Abby now lives to be by her side when she goes into labor. Meanwhile, Kirkendall and Russell look into the theft of a graduate film student's camera, where only the student seems more interested in dispensing his own justice. Also, Sylvia finally learns about Sipowicz's medical condition from his doctor and finally persuades him to go for further tests and possible surgery.

Simone and Sipowicz look into the shooting of two women (one of whom was killed) who were raped by a group of men in an apartment owned by a former crack dealer, named Jamal, who was crippled in a previous shooting incident. Sipowicz confides in Simone about his medical condition when Simone sees Sipowicz's doctor pull him aside and talk to him confidentially. Meanwhile, Kirkendall, Russell and Medavoy investigate a shooting at a clinic. When they get a woman suspect into custody, a security guard from the clinic who was her secret admirer comes to the precinct demanding she get a second chance.

The detectives get a break in a case involving a police officer suspected of committing murder.

As Sipowicz prepares for prostate surgery with Sylvia by his side, James Martinez returns after recovering from his back problem where he reports that Gina had her baby three weeks earlier. But Medavoy is even happier after returning from upstate New York with a videotape of Abby giving birth to her baby and is very eager to show the tape to anyone who will watch. Meanwhile, the rest of the squad gets involved in a case of five reuniting Army buddies when one of them is found dead. The four others try to keep their fabricated story straight as Simone and the others try to figure out their involvement.

Sipowicz returns to work after his successful prostate surgery, but apparently too soon, for he has an accident while interrogating a suspect. He is given desk duty to help Simone and Russell investigate the murder of a woman's boyfriend by her ex-husband, the ex-husband later revealed to be searching for his daughter who's gone missing while in the ex-wife's care. Meanwhile, Simone is called upon by Detective Nick Savino to help investigate a missing persons report that is being filed by the nephew of one of Simone's apartment tenants. Based upon past exchanges between the missing woman and Henry Coffield, another building tenant, Coffield becomes a suspect. Former administrative aide Naomi Reynolds shows up at the station, now wearing a private security uniform and speaking in her natural Australian accent, to visit Simone, hoping to tell him that her situation with the INS was resolved and she is now furthering her pursuit to one day become a NYC police officer.

A murdered couple is found where the dead man is a car salesman and the woman is a prostitute. Simone and Sipowicz look into the salesman's death, while Medavoy and the other detectives look into the prostitute's death, where the M.O. of the suspect is to buy used condoms from a prostitute and then mix the spent semen with his own to cover his crime. As Sipowicz recovers from his surgery, he finds that a recent blood test is not favorable and once again keeps his medical problem to himself.

Simone and Sipowicz work with Cohen to investigate the death of one of Cohen's witnesses and her son. Evidence points to the opposing attorney having some involvement with the arrangement of the homicide. Meanwhile, Russell and Kirkendall try to help a man locate his missing daughter. Medavoy and Martinez look into a corporation dealing with fake sports memorabilia, where Medavoy is taken in with the blond employees who reminds him of the departed Donna. Also, when Sipowicz thinks about his low sexual functions, his doctor prescribes the wonder drug Viagra. In the mist of all the cases, Simone and Russell decide to get married on their lunch break, but their cases get in the way of it all.

The detectives investigate the torture-murder of a hotel magnate's son. Russell and Kirkendall suspect that an attempted rape victim is hiding something. Simone's health begins to deteriorate.

The detectives of the 15th Precinct investigate a double homicide involving one of their own, an alcoholic cop who seems to have done the right thing, but can't remember key details about the incident.

The detectives question a group of unsavory suspects after a well-dressed man is found dead in a park. The squad tries to stay optimistic as Simone is told that he will require a heart transplant.

The detectives investigate a grisly murder in which an elderly woman's hands and feet were cut off. Simone's health continues to deteriorate.

Sipowicz helps his ex-wife deal with a drunk-driving violation. Simone's body rapidly succumbs to infection in the wake of his heart transplant.

Youthful detective Danny Sorenson joins the squad and, during a multiple homicide investigation, discovers that his new colleagues have yet to recover from Simone's death.

Sorenson and Sipowicz investigate the beating death of an elderly shop owner. Russell and Kirkendall encounter Dolores while investigating a homicide at a strip club.

The detectives search for the truth when a white off-duty police officer with a history of racism fires upon an African-American undercover cop. Dolores is arrested for shoplifting.

Kirkendall's son witnesses the murder of a convenience store clerk. Medavoy and Martinez investigate the death of a homeless man.

The detectives find themselves caught between the F.B.I. and Internal Affairs when an off- duty officer is killed during a robbery. Medavoy falls victim to Sipowicz's mischievous prank.

ADA Costas prepares for the trial against Cullinan, and chooses Sorenson to testify over her husband. A man is shot dead in his apartment, and his wife's story about Latinos looking for drugs doesn't add up.

Tensions mount as the Cullinan trial approaches. Mike Shannon brings a problem to Sorenson. Danny kisses Diane. There's a shooting at the courthouse.

Tensions mount as the Cullinan trial approaches. Mike Shannon brings a problem to Sorenson. Danny kisses Diane. There's a shooting at the courthouse.

Janice is promoted from vice squad officer to detective and will be working with the other detectives until she can be transferred to the re-organizing intelligence division. Meanwhile, Kelly suspects that his friend, Charlie Lear, is being framed for the murder of his mistress, even after his erratic behavior in the squad room points to his guilt. Fancy's wife tells him that she's pregnant again and he is less enthusiastic considering the complications of her two previous pregnancies. Also, Sipowicz falls off the wagon when he starts drinking again at a birthday party for Sylvia's father.

Medavoy suffers a stress-related anxiety attack while working and doesn't want to tell his wife about his personal problems, which displeases Donna who wants him to work things with his wife. Meanwhile, Sipowicz looks into the robbery of a wheelchair-bound Vietnam veteran, who later takes his muggers hostage. Elsewhere, Detective Kelly starts moonlighting as a bodyguard for Robin Wirkus, the young girlfriend of Jimmy Wexler, an ailing wealthy friend of Kelly, and Kelly later stumbles into a complex blackmail plot by an extortionist, named Stan, who asks Robin for sexual favors. Also, Laura tells Kelly that she have moved on with her life and is dating someone.

Simone and Sipowicz investigate a claim of sexual assault against a mentally disabled 17-year-old schoolgirl, after her domineering and verbally abusive mother reports it. They try to persuade her to press charges against the two assailants. The alleged assailants are from privileged backgrounds who attend an exclusive prep school. One is the son of sleazy councilman Paul Manos, with whom the detectives had problems a year earlier. Meanwhile, a young man who speaks only gibberish, known to Sipowicz who had him committed four years ago, appears at the station and causes a minor scene -- trying to get someone to listen to him about a problem he now has. Sipowicz investigates. Meanwhile, Russell continues her undercover work and relationship with Jimmy, who shows off his true psychopathology when he beats up a roller blader who had accidentally bumped into Russell.

Simone and Sipowicz investigate the race-related murder of a Puerto Rican teenager who was attacked while spray painting graffiti in Little Italy. Meanwhile, Medavoy meets Donna's former boyfriend, Harold, when he comes to the station to file a car vandalism report, while Donna makes a tough decision about her relationship with Medavoy. Also, Sylvia is mugged and she later tells Sipowicz a secret from her past about being raped as a teen.

Sipowicz has a cavity and decides to have it taken care of by his son's dentist. At the dental office, Sipowitz finds himself unsuccessfully trying to prevent the suicidal Dr. Fleishman from jumping off a 28th floor ledge. Meanwhile, Medavoy and Martinez work on a strangulation murder case that appears to be the work of a cross-dresser. LaSalle's first case for the squad involves a woman who was raped and she, Kelly, Sipowicz try to catch the most probable suspect. Janice joins the undercover squad and is partnered with the hot-tempered Roy Larson to assist with LaSalle's case, while Sipowicz suspects that Larson's short temper and odd behavior points to a drug problem. Also, Lois Snyder (the prostitute who set Sipowicz to be shot in the premiere episode) returns to try to apologize to him about the incident and also wants to renew their romance. But Sipowicz turns her down and goes back to start whatever relationship she has with D.A. Sylvia Costas.