The detectives hunt for clues relating to a missing college freshman. Their hope of finding her alive diminishes as all of their leads on her turn cold.

A woman is found dead in a locked room while another died when her car is hit by a train.

A casino was brutally but clumsily robbed by at least four trigger-happy fiends, the men of which wore female wigs. Painstaking identification efforts lead to ex-con serial killer Tammy Felton and accomplices, but one by one is found murdered themselves. The solution comes only after links are found with the bizarre shooting of a desert hamlet's only store's clerk, discovered by state trooper William Spencer, who messed up the crime scene despite long experience.

A staged suicide harks the return of a serial killer. Catherine and Gil Grissom, while at court, finds the the residing judge looks exactly like this killer. Grissom investigates the judge's past and finds a startling answer.

A young woman is found dead inside a heavily secured house. The position of her body strikes a chord in Nick's memory, prompting him to believe that he might be the next target.

The owners of a house placed on sale are found dead, their bodies discovered by two interested buyers. Sara is working solo on the death of a cheerleader at a high school.

A dwarf is found dead, hanged in an auditorium during an annual convention for little people. Working on a case of murder during a home invasion, Catherine is attacked by the perpetrator while processing the scene.

During a magic show, a female participant really disappears during a disappearing act. Nick and Catherine investigates the death of a rock star found on his tour bus with a needle stuck in his arm.

A murder is caught on tape. With no body or a crime scene, Sara, Warrick and Catherine must get as much information as possible from the grainy 16 mm film. Grissom and Nick must brave a colony of fire ants to recover a body.

Matt Phelps sends his two kids to bed, and out of the blue, there is a drive-by shooting and his daughter Aimee is shot and killed in her bed. Grissom, Warrick and Capt. Brass investigate the case and Grissom learns that Matt Phelps is Warrick's mentor and friend. Warrick's investigation is conducted based on his emotions instead of on the evidences with serious consequences for Matt and a suspect. Meanwhile, Nick and Sam Vega investigate the mysterious death of a boss of a four-men Internet service company in the air-conditioned servers' room. They find many secrets in the team but no suspect and no murder weapon. Until Nick observes the duct of the air-conditioning.

When a body is found in a foam party, he is identified by Grissom and Capt. Brass as the male prostitute Trey Buckman. Meanwhile, Catherine and Nick investigate a decomposed body of the also male prostitute Croix Richards in his apartment. Catherine receives a phone call from Eddie's phone, who is with Lindsey, with poor reception, but soon she learns that Lindsey is screaming and she leaves the crime scene to seek out her daughter. She finds Lindsey in a car in the water but she rescues her. Sara and Det. Vega investigate the case and they suspect that Eddie is dead. Meanwhile Grissom concludes that both victims may have been dead by insulin and they were employees of Lady Heather. Grissom and Catherine visit the suspect Rebecca and meet her husband Steven McCormick that tells to them a weird story. Then he goes with Capt. Brass to Lady Heather's house. Grissom has a personal moment with Lady Heather and when he learns that she is diabetic, he requests a warranty to get her insulin.

A man is found stabbed to death in an art house cinema while a young shooting victim is found in a storage room with a bizarrely wide bullet hole pattern.

A couple of high school students find the body of a woman in the press box of football field. Grissom, Nik, Sara and Capt. Brass investigate the case and they learn her identity, the waitress Alison Carpenter. Their further investigation lead them to the former prison inmate Jason Kent, who has recently been released. Alison was his girlfriend and was having sex with the drug dealer Jesus to postpone the debt of Jason with him. Meanwhile, Greg's DNA laboratory explodes and Sara and him are injured. Warrick and Catherine are assigned to investigate the case and find the responsible for the accident.

Several couples are killed bloodily after a wild party night in the same luxury hotel with Cameron and Mandy Klinefeld, or rather one somehow forced to kill the spouse. Nick is pleased to bump into former college mate Kenny Richmond, who works there, until it seems buddy boy passed confidential information to the press, which could get Nick fired.

A grossly decomposed corpse in a bath tub is identified as frat student Daniel O'Hannissey. He was last seen in a bar, taking part in a brawl about team sports, but left apparently unhurt. Meanwhile, the serial couples killings investigation takes a sharp turn when both are murdered in their home, while the undercover police observation was diverted.

During a week-log heat wave, corpses are found, mostly accidentally. A.D.A. Jeffrey Sinclair decides to 'make an example' of a workaholic father who forgot his baby-boy in his scorching-hot car with fatal result, but the team finds the couple lost a previous baby and may have murdered this one. Mark Young is missing since his teen date's fatal lake sports accident. A fat man on a crazy diet was electrocuted at home.

Julie Waters, a dancer, has been missing for 6 days. A suspect, Howard Delhomme, calls the police and turns himself in. He refuses to talk to anyone but Catherine. Sarah and Nick want to work on this case because they see it as a career-making step. Grissom, to their anger and disappointment, hands the rein over to Catherine. Despite their initial antagonism, they all worked together to find the young girl.

Teenager Brian Haddick is found on a construction site, skull fatally smashed, with an employee's hammer. Grissom's team checks on the construction crew as well as Brian's school crowd, stumbling on abused love and dirty practices. Another victim was killed by a bullet which literally fell from the sky.

While trying to pass a bus on the highway, an arm strikes the windshield of the car of a couple. Catherine, Nick, Sara and Capt. Brass investigate the crime scene and find pieces of a woman secured by white strips of clothes on the bottom of the bus that was carrying inmates from a prison to a church. They believe the woman was trying to flee from the correctional facility. Soon they learn that the victim is Antoinette "Baby Girl" Stella that would be released on the next month. Sara and Nick go to the prison to try to understand why Baby Girl decided to escape. Meanwhile, Grissom and Warrick investigate the murder of Adanto Adams who was stabbed to death at the home of his intellectually disabled brother Zero. Soon they meet Zero and his guardian Frank Samuels and they learn that Adanto has promised to his beloved brother Zero that they would be rich. Warrick gets the videotape of the casino where Adanto went to play blackjack and lost a fortune.

A strong and tall man follows another man in the casino to the parking lot. Soon the CSI team comes to the casino to investigate the murder of the man, Tony Sciarra, who was brutally beaten. They watch the tape of the surveillance cameras and see a shorter man stealing Tony's chips and being followed by him. When they identify the killer, Walter Darian, they arrest him; however, the guy attacks Grissom first in the interrogation room and then the guards that try to subdue him. Out of the blue, Walter is dead. Now, they investigate his belongings since he was an accumulator and find evidence that may lead them to another murder case.

Greg has found a replacement in the DNA lab, Chandra Moore, and introduces her to the co-workers. Capt. Brass, Grissom and Greg, in his first case, investigate the death of an unidentified victim with a shot in the forehead in a shooting in the nightclub owned by Manny Brazil. He says that he does not know how the gun has passed through the metal detector. Catherine and Det. Louis Vartann investigate the murder of a woman covered in blood in a hotel room. The man, Carl Johnson, also covered in blood, tells to the detectives that he has never seen that woman before. Soon they learn that the victim is the stripper Nicole "Raven" Richards that drugged Carl to rob him. Warrick and Det. Chris Cavaliere investigate the death of Lance Frazer, a loser that died in the bathtub electrified by heat exchanger causing a short circuit in the motel. Soon Warrick learns that Lance hit a fifty-thousand-dollar jackpot on the previous night. Nick, Sara and Det. Travis investigate an "alien" buried in a shallow grave near the Area 51.

When April Perez reports that her thirteen-year-old Alicia Perez has been kidnapped by an Afro-American man driving an old Buick, the CSI team investigate the scene and an Amber Alert is issued. Capt. Brass interviews the parents Sybil and Carlos and he learns that April had drug problem. Meanwhile, Grissom and Sara look through Alicia's room and Sara learns from Alicia's brother Daniel that his sister was in love with her schoolmate Jimmy Jones. When they meet Jimmy, the boy tells them that Alicia was upset since she would have to donate her kidney to Daniel and she liked to play soccer. When they find the body of Alicia dumped on the road, they make news discoveries about the case.

While driving her convertible at high-speed in the highway, a woman is stopped by a patrolman. Catherine and Grissom arrive later to the highway where the woman was found with slit throat and slashed genitals in her car. They also find a camcorder with no tape on the floor. The entire team investigate the case and Warrick and Sara find documents in the car, showing that the victim is Wendy Garner and the car's registration and the driver's license in the name of Walter Clancy. When Dr. Robbins finds a prostate in the victim, the team learns that she was a transsexual, and soon concludes that Wendy and Walter were the same person. When Grissom and Brass investigate Wendy's fiancé Aaron Laner, they learn that he does not know that Wendy was a transsexual. The team also interview her fellow dancers and learn that Dr. Mercer is the responsible for most of the transsexuals' operation. However, the doctor tells Catherine and Warrick that he refused to operate Wendy since she wanted to jump steps of the procedure required by the law. Now they are looking for the surgeon that might have operated Wendy.

Greg is doing his final proficiency test and he has a case to solve. Ironically, he investigates the death of a Sherlock Holmes- wannabe, obsessive to the point of recreating the great detective's living room in his home. He died from a close-range gunshot wound. The murder weapon is not found in the scene although everything other pieces of evidence suggest that it was a suicide. Working under Catherine, Nick and Warrick works on a case of a dead guy found in his car which veered off the highway. Dr. Robbins cannot find the cause of death and it is left to the two detectives to solve the mystery.

When the university students Paula Levine and Trip Wilmont are found dead on the floor after having sex in Trip's dormitory room, Grissom, Sara, Greg and Capt. Brass investigate the case. Grissom leaves the case since he has to go to the court and Sara and Greg use the monoxide carbon detector to look for a source, but they do not find any monoxide carbon in the room. Meanwhile, Brass talks to his next-door neighbor Zack Capola, who says that Trip and him were just mates, not friend. Sara and Greg proceed the investigation. Meanwhile, Catherine, Warrick and Nick join to David Phillip in the middle of a crop circle to investigate the death of a man. In the autopsy, they learn that the victim has urinated in his underwear. When the CSI team locates the owner of the helicopter that was in that area, they learn what has happened to Kevin Staniland. Meanwhile, Det. Louis Vartann finds that no investigator is available and Conrad Ecklie is forced to go with him to the Tangiers since there is a dead body needing to be processed. They learn that the victim is James Billmeyer from New Jersey and Ecklie requests the shoes of the woman that found the body since she stepped on the blood. When James' body vanishes from the morgue there is a further investigation.

While investigating a case, Nick is abducted and is buried alive in a special coffin while his team takes unorthodox steps to try to find him.

With its desperate attempt to ransom Nick's release failed by their enemy's fanatical revenge, the CSI team must use all their investigative talents to find Nick, whose perilous situation is becoming all the more horrific by the minute.

CSI team goes back to investigate crime scenes as a team, re-united together after the traumatic experience in season five finale. Nick's kidnap case audio tape arrives at the laboratory.

An up and coming movie star is found dead in his hotel room after partying with groupies. In another case, a dead cab driver leads the team to a string of deaths involving immigrant workers.

When a woman dies on her staircase, the team uncovers marital infidelity and an even bigger secret during their investigation.

Nick arrives at the house of Jude McBride and the sheriff explains to him that they received an anonymous call reporting a possible crime. There is blood everywhere inside the house including three large pools. Nick learns that the Jude, Nina, Jeremy and Cassie McBride are a happy family and they are missing. Sara arrives in the house and tells to Nick that Grissom is at a conference. Then Warrick and Greg also arrive to help the investigation. Soon Sara finds a marijuana farm in the basement of the house. They also find that the anonymous phone call had called several times the family phone and they locate the caller, the local Dr. Malcolm Parker. When the laboratory discovers the identity of one fingerprint, the case begins to be resolved.

Catherine investigates the murder of a young mother who claimed God got her pregnant, while Grissom witnesses a very shady trial.

The CSI team is called to help when Karen Mathews reports her son, Jesse, missing from a playground where he was playing on the swings. Witnesses report seeing a man with a blue baseball cap near the swings. Clues in the park bathroom include blood and the boy's underpants. The boy is eventually found in a store, accompanied by a woman with a man fitting the earlier description. But the couple with the boy claim that he is their son Adam, while Karen insists he is her missing son Jesse.

The CSI's investigate the death of a very hairy man. At a quick glance, the body can be easily mistaken for a werewolf. The man died from a gun shot wound. He, along with his sister, has a rare genetic disorder which causes excessive hair growth.

The murder of a man in a garage leads the CSI team to the daughter of the man who abducted and buried Nick alive earlier.

Someone tries to kill a diva called Lois O'Neill, who was related to the mafia years ago, and a waiter is killed instead. The CSI investigates the case, but more than ever, nothing is what it seems.

A man walks into a shabby apartment and shoots the occupant. On his way home, a teenager's car crashes into his car. Ally Sullivan insists on calling the police but the man refuses. As he leaves, he sees her texting her phone. Thinking that she's calling the police, he kills her. The CSIs have a hard time finding this killer as he knows how to cover his tracks really well. He is truly a professional.

A woman is coming home staggering when her neighbor Christina Hollis stumbles into her crying, bleeding and nervous, since she has been raped. Grissom and Catherine investigate the case and are followed by a camera and a television crew of a reality show since the sheriff has authorized them believing that it would be good for the image of the department. They collect evidences from the apartment. Sofia interviews Christina in the hospital but she has no recollections of her assault. Their first suspect is the maintenance guy but his duct tape is different from the one used in Christina. Archie examines the elevator camera and sees a young man with flowers getting off at her floor. Later he is identified as Dwight Reynolds, who used to date Christina. Soon they believe the person of interest is a fireman. When the team crosses Christina's case with other recent cases, they succeed to find the suspect.

A psychic is murdered in her own shop after predicting her own death.

A criminal defense lawyer is murdered at her son's wedding and tied to the back of a car with beer cans. It is later revealed that she had a bad attitude at the bride, the groom's father, and basically everyone else.

When a man is found dead in an alley wearing expensive clothes, Grissom and Catherine meet Capt. Brass at the scene. They collect evidences and find a room key from the Palermo hotel in his pocket. Soon they learn his name, Jeff Powell, and he was driving a Ferrari with a sexy blonde. They identify the blonde as Heidi Wolf, who had one-night stand with Jeff. She says that he felt in love with her, but she did not want a long relationship. Capt. Brass and Grissom interview Jeff's boss, Los Angeles' producer Mick Sheridan, who tells them that Jeff was his assistant and saved millions of dollars in his divorce. So he was rewarded with a dream trip to Las Vegas. When Det. Sofia and Nick located the rented Ferrari, they find small damages and soon they discover that a black Corvette was the responsible. They interview the driver, Randy Bolen, who admits that lost a large amount to Jeff in a single game. When they learn that the Caprice Unlimited rented the Ferrari and the Corvette, they find that the company realizes clients' fantasies and they start to solve the case.

A group of dead bodies in the Las Vegas morgue get to know each other while CSI tries to solve the crimes that got them there.

Greg has his day in court for running over and killing a street gang member right before his own beating, and a second crime scene replica is found--this time after the murder of an elderly woman.

CSI investigates the deaths of estranged identical twins: one from a gunshot wound, and one from an apparent suicide. The two deaths do not appear to be related, but are they?

The team searches for a link between a current string of murders in Las Vegas and a notorious mob boss who disappeared in the 1970s.

When one Trenton cop is murdered in Las Vegas, a second threatens to expose Keppler's past if he doesn't make the case and the evidence go away.

Grissom thinks the miniature killer is dead, until he receives another miniature crime scene. However, unlike the others, this one predicts a crime scene that hasn't happened yet.

A star high school basketball player disappears, and the investigation reveals that he gave an STD to a couple of his classmates.

Six showgirls who live together are murdered in their home, and Sara is distressed when the final victim dies in her arms. However, she may have left Sara a vital clue that could help her ultimately identify the killer.

With Grissom out of his office and all of the detectives out in the field, Hodges and the lab other techs try to discover new clues in the miniature killer case.

CSI discovers that a woman may have been murdered, and her head mounted on a wall as a trophy, because the killer was convinced that she was actually a powerful alien reptile.

After an unsuccessful attempt on Lady Heather's life, Sara discovers Gil's prior relationship with her. Meanwhile, Nick investigates the death of a woman apparently hit by a taxicab.

The parents of a missing girl are found murdered in a seedy motel room, and a registered sex offender now working as a church pastor is suspected. Meanwhile, Sara tackles a case involving a dead homeless man.

The hanging death of a possible hermaphroditic male is connected to a tainted water supply, while the day crew investigates 40-year-old skeletal remains found at the site of a recently-imploded casino.

The investigation into the death of a popular slasher movie actress is complicated by a series of frame-ups, double crosses, and blackmail attempts.

A young boy and his babysitter are murdered. The case is similar to an open child abduction case, so FBI agent Jack Malone comes in to investigate. Part one of a crossover with "Without a Trace."

The murder of a co-ed leads to the investigation of a brother and sister who were involved in another murder case from Sara's past, and the case drives Sara over the edge.

Hodges puts the lab techs through a series of "murder games"--a set of bizarre, hypothetical murder scenarios which all take place in the lab.

Two dead bodies lead CSI to an old-school mobster who runs a strip club. Meanwhile, divorce proceedings and prescription drug addictions cause Warrick's life to begin spinning out of control.

CSI investigates three related deaths that take place during the Las Vegas bull riding championships.

The discovery of the body of a witness shot in a burned-out car could compromise the DA's case against the leader of a Latino gang. But was the gang really involved in the witness' murder?

CSI investigates the death of a toddler who was left in a cardboard box in a parking lot. A registered sex offender who is wrongly accused threatens Catherine after the real cause of death is identified.

A nightclub owner serving time in prison gets a temporary leave so that he can help Brass and Stokes investigate a double homicide with several connections to him.

While investigating a series of unusual deaths, the team discovers that all of the victims are tied together through a strange set of circumstances.

A mobster that Warrick had a run-in with is found dead, and Warrick is found at the scene with the murder weapon. However, he insists that he has no recollection of the crime.

CSIs past and present come together at the news of Warrick's death. But will Warrick's real killer successfully frame another police officer for his murder?

A woman's unlikely suicide is tied to a bank robbery and a hypnotist, the team investigates the murder of a guidance counselor who was also a degenerate gambler, and Sara helps out in an euthanasia case.

When CSI investigates a homicide that appears to have connections to the S&M world, Gil turns to Lady Heather for help. But is he really there because of his personal problems with Sara and not for the actual case?

CSI needs the help of an 8-year-old, HIV-positive boy to figure out who shot and killed his uncle and his mother during a street party in Koreatown.

A man blames the anonymous sender of emailed death threats after his wife and daughter are shot. Two teens in a convertible crash into a tree; one has an inexplicable shoulder injury. Grissom attends a transfer hearing.

When a finalist for a popular television amateur singing competition is killed, it sheds new light on a 50-year-old murder at what was the first integrated casino on the Las Vegas Strip.

When a new murder leads to a connection with an infamous serial killer, Grissom secretly joins the class of well-known criminal pathologist Dr. Raymond Langston to gain access to the killer and get a crack in the case.

Grissom gets Dr. Langston's help to find the man who is carrying on the serial killer's work before the next victim is killed. The case will prove to be Grissom's last with the crime lab.

Dr. Langston has a challenging first day learning the ropes both in the field and in the crime lab, and the team has a difficult time deciding who will get Grissom's old office.

The unit takes on cases involving two employees killed after hours in a chicken restaurant, and a struggling mortgage broker's wife who was killed from swallowing a lethal amount of toothpaste

CSI gets three new dead bodies, and all three cases have a connection to the same con artist with multiple identities.

Nick volunteers on his birthday to take a case involving a 16-year-old girl found dead in the parking lot of a seedy hotel, because he got to know the girl while investigating other cases at the hotel over the last year.

Nick and Riley investigate the case of a badly injured skydiver, while Dr. Langston investigates the death of a religious leader out in the desert.

Will a case involving a television producer killed during a sci-fi convention kindle an unlikely romance between Hodges and Wendy?

A case from Catherine's past is reopened when a man who has been in prison for 18 years challenges the evidence that convicted him.

A biker who is brutally stabbed to death in a biker bar turns out to be an undercover agent whose cover was blown.

A mild-mannered operations support employee kills one of his co-workers. But while CSI is busy trying to figure out the killer's identity, the motive for his crime is revealed.

The case of two high school students, one dead and one missing, lead the CSIs into the underbelly of streetcar racing and a tangled web of deadly competition.

Catherine and Nick try to find out how a member of the band Rascal Flatts was nearly electrocuted during a concert, while Ray runs into roadblocks while investigating the death of a retired CIA chief.

The team tries to figure out how and why a 14-year-old boy broke into the evidence facility and tampered with the evidence in an old murder trial, which led to his accidental death.

While Catherine helps perform surveillance on a pair of meth dealers in a casino hotel room, Archie accidentally stumbles on the dead body of a casino hospitality employee in the loading docks.

Hodges and Wendy pose as CSIs to impress a group of "Crime Cadets" and get some help in solving a crime, and Hodges becomes jealous when Henry asks Wendy out. Meanwhile, Nick and Greg solve a bacteria outbreak at the police station.

A dead reporter is found with pictures of the victims of "Dr. Jeckyll" on her, and the investigation into her death reveal some disturbing secrets about Dr. Langston, past and present.

A badly shredded body is found in the back of an 18-wheeler, and the shredded remains of a credit card at the scene suggest that the CEO of a shady identity theft company is involved.

The deaths of a rancher and an engineer are tied together by their connections to a tainted water supply and the small-town newspaper reporter trying to expose it.

The CSIs set out to track down a pedophile suspected of murdering an FBI agent's wife and kidnapping his children.

A prostitute is found dead at the same site where a staged photo of the same dead person was taken and posted on a website days earlier, and Hodges theorizes that the parts on his new motorbike were in a fatal accident.

While the team searches for a killer who is killing his victims with an electric chair, Greg falls for a classic film noir "femme fatale" who may be connected to the case.

The death of a prominent professor in the deaf community is connected to a feud between two deaf graduate students competing over a grant, and the investigation creates tension between Sara and Grissom's mother.

When two people who were thought to be dead come back to life, the evidence leads CSI back to a discredited ex-professor who conducted bizarre death-related experiments in the 1970s.

Dr. Langston turns to Lady Heather for help in the murder of a woman who acted like a cat, and Nick tries to figure out what caused a pregnant teen to commit suicide after he saves her baby.

While the team discovers body parts of a man and a woman in a barn, a ransom video involving one of Nate Haskell's brides arrives at the crime lab. They soon discover that the two cases are actually connected.

The skeletal remains of three people are found in the desert. Initially beetle evidence implies they had been dead at least a week but other factors contradict that. They bodies were identified as a lawyer, that Catherine had a connection with, and his two employees. Catherine had recommended the lawyer to a friend, who was trying to escape her dangerous husband. After analysis the beetles appear to be genetically altered. Catherine fears her friend could be dead until she makes contact with a location.

The team discovers that a WLVU student notorious for his gossip video blog was killed because he was about to expose a major campus scandal.

The task of figuring out who shot and killed a pediatrician in a casino becomes more difficult when the team discovers that the killer is one of three identical triplets.