A kidnapped girl is the victim of police shooting. Abby is stuck in the middle of a disagreement between Luka and Clemente. Neela receives a phone call from Iraq. Later, Luka and Abby share a kiss.

The ER prepares to take in victims from a plane crash while Neela and Pratt head out to the crash site where Neela makes heroic efforts. At the end of the day Neela gets a surprising visit.

As Abby and Luka cope with their newborn's life and death struggle, the couple is shocked to receive a surprise visitor: Abby's mother Maggie. Meanwhile, Sam fears the prospect of criminal charges; Neela discovers that Tony Gates will be joining the ER team as an intern and Morris gets his job back while Weaver gets demoted.

Gates is assigned to the case of a closeted gay man whose partner clashes with his family; Neela meets her new surgical chief, Dr. Crenshaw; and Pratt must cope with the flood of new interns.

Abby and Kovac discover both the joys and difficulties of raising a newborn; Morris is wrongfully accused of being a child molester; Pratt has his trial-by-fire when he has to handle the ER alone, juggling multiple traumas, teaching duties and a troublesome intern. Neela continues to be the target of her difficult supervisor, and Sam discovers her sons latest extra-curricular activity.

Curtis Ames, a carpenter who suffered a stroke under Kovac's care, sues him for malpractice. Kovac and Ames square off in court as each man's recollections of Ames' treatment are recounted via testimony and flashbacks. Meanwhile, Abby returns to work and must adjust to the dramatic changes in her life, and Pratt's early morning trip to the barbershop results in a new awareness of community need. Also, Abby and Pratt try an unconventional method for treating a heart patient and Neela tries a risky procedure which doesn't sit well with her chief.

Kovac anxiously awaits the verdict between himself and Curtis Ames but fears the worst. Meanwhile, Neela disobeys her chief's orders and also questions her feelings for Gates, and Weaver unwittingly steals the spotlight from Morris in his big television debut.

A belligerent young man who claims to have the flu turns out to be more than he seems, and presents a challenge to Morris and Sam when he refuses treatment. Abby's chance encounter with Curtis Ames leaves Kovac uneasy. Meanwhile, Pratt discovers a local church's risky drug exchange program, Neela and Gates square off, and Weaver gets an interesting offer.

A mysterious illness leaves little hope when a group of homeless kids enter the ER and one of them believes that Neela is a guardian angel in blue; Abby and Kovac clash over a possible case of domestic abuse; Pratt makes a shocking discovery about his brother, and Weaver is unexpectedly called into action when her television appearance becomes a real emergency.

Thanksgiving at County is quiet, with the normal number of routine (or nearly so) emergencies. But Abby makes up for the lack of excitement while returning to the hospital as the doctor on a helicopter transport.

Kovac and Gates treat a girl who appears to have been assaulted. When the police are no help with Ames, Kovac decides to confront the problem himself; Morris and other doctors work on a patient with an ice pick in his ear. Meanwhile, Ray tries to keep his new relationship a secret and Pratt can't fully deal when his half-brother officially comes out. Also, a new male nurse arrives.

It's Christmas in the ER. A homeless boy sends Gates and Ray on a mission. Meanwhile, in the ER, Neela oversees an unusual kidney transplant case; Sam takes a stand when a patient is dumped in an alley by another hospital; and Morris plays Santa for a special girl and learns the meaning of Christmas.

Weaver cares for a Katrina survivor who's reluctant to have surgery on her foot; budget cuts force Luka to make a difficult personnel decision. Also, Gates' home life intrudes on the ER; and Pratt and Hope are shaken after a patient in their care dies needlessly.

Kovac reacts negatively when he sees Abby giving extra attention to a patient; Ray and Gates clash over a patient, pinning Neela in the middle; and Ben takes things to the next level with Sam. Meanwhile, Pratt is under investigation and Weaver says a final goodbye to the ER.

Kovac finds himself in a tense confrontation with Curtis Ames, and Abby must act to protect her family. Meanwhile, Neela and Gates rush to get Meg to the hospital while Sam's new home is soon under threat from fire.

Abby and Sam try to treat an aspiring comedian with mysterious symptoms; Pratt must defend his actions in front of the medical board; Neela scrubs in on a kidney donor transplant; and Morris, as the lone attending, must run a busy ER. Also, Kovac gets a surprising proposal from Abby.

Kovac and Gates find themselves with a moral dilemma when a woman comes into the ER with acute liver failure; Neela finds herself questioning what is right when Manish decides to give up a kidney to a complete stranger. Meanwhile, Ray fights to get to the bottom of a cheerleader's accidental fall; Abby gets a prediction for her future; and Alex's troubles continue to intrude on Sam's work life.

A blizzard strands a family in the snow and Abby and Pratt quickly try to save the family. A gang shooting challenges Morris and Pratt. Meanwhile, Kovac and Abby begin making wedding plans, but their engagement might not be very secret; Gates struggles with the reappearance of his father and the possibility of losing Sarah; and Neela becomes jealous when Dubenko brings in a new surgical intern.

It's Sam's birthday, but she finds it hard to be away from her son Alex. Meanwhile, Sam meets a photographer taking pictures of a terminal patient and she gives Sam a new perspective on life. Dubenko's new surgical intern unsettles Neela during a trauma; Gates is shadowed by a new and nerdy intern and later must tell Sarah the truth that he may be her biological father. Also, Morris and Hope annoy Kovac and Abby when they try to help with their wedding preparations.

Kovac and Gates deal with a hopeless father whose son succumbs to heart failure; Pratt tries to resolve the tension between him and his brother; an Armenian man tries to be a good samaritan but ends up crashing near the ER; Abby sneaks in baby Joe when she worries his sickness may be worse than it seems; Also, Sam injures the instructor of a self-defense seminar.

In 12 hours, the ER will shut down. As Kovac is under pressure to take care of the patients before the final hours, he makes a pivotal decision about his future. Meanwhile, Sam befriends a photojournalist who returns only this time she's terminally ill; Pratt is concerned when his brother ends up in the ER drunk; Morris confronts Gates when he ignores his orders and angrily sends him home while Gates tries to defend his actions.

What is supposed to be a departmental dinner organized by Kovac turns out to be the surprise of a lifetime for Abby when she learns it's a surprise wedding, secretly planned by the eager groom. Meanwhile, at the wedding, ER staffers enjoy themselves with music and booze while Neela finds herself the center of unexpected attention between Gates and Ray, which leads to a drunken fight and a shocking conclusion.

The ER reopens with new changes. However, the ER is not the only thing that's changed; Kovac and Abby adjust to being newlyweds; Morris and Hope enjoy themselves at the honeymoon suite; Pratt attempts a change for a woman; Neela worries when Ray goes missing; Meanwhile, there's a new doctor in the ER and he means business; and another change may come when Kovac receives a phone call.

The ER is now in the hands of a new chief, Dr. Kevin Moretti, who is bent on major changes. Meanwhile, a phone call leads Neela to a hospital where a major shock awaits her, and a final farewell from a friend and colleague. Gates urgently goes home to stop Sarah from being taken away from him. A drug-addicted Iraq War veteran baffles Morris and Sam. Also, Kovac postpones the honeymoon and says goodbye to Abby and his son, for the meantime, while he travels to Croatia to visit his ailing father.

Abby, Pratt and Morris clash with Moretti's strict new ER procedures as victims of an anti-war rally roll in, including Neela. Gates manhandles a patient he suspects set off the explosion that disrupted the protest. A worried Dubenko lets his emotions for Neela take over during Neela's surgery. Meanwhile, the rest of the staff worry over Neela's condition.

Patients include a pregnant teacher whose student/lover was critically injured while driving; a man who is hiding a gunshot wound and a brilliant young boy who knows he is dying, but hides it from his mother. Dr. Moretti continues to remake the ER to his liking, Neela is recovering, Luka's absence is reinforced (back in Croatia and not coming back) and Sam may be starting a new relationship with a police officer.

Abby and a distracted Morris work to save two auxiliary cops brought in with gunshot wounds. Pratt treats a teen wrestler with severe vomiting, but the problem is much more serious. Sam worries over her new beau Litchman. Gates tries to help a young boy in the ICU with a deadly disease. Also, Dubenko visits Neela while she babysits baby Joe.

When Baby Joe is injured by a fall at the playground and rushed to the hospital, Abby is unable to reach Luka to tell him.

Moretti reassigns Gates back to the ER and treats a couple involved in a car accident. Morris prepares to take his written board exams. Neela is assigned a young genius intern. Kovac plans to extend his stay in Croatia while Abby struggles with single parenthood.

Moretti brings in new attending Skye Wexler to help with the patient load. Morris and Pratt cram for the medical board exam. Gates treats a returning patient from the ICU whose condition has worsen. Sam tends to a teenage girl who is feeling neglected by the staff. Neela's intern, Harold, seeks her advice on a personal matter. Abby struggles with her relapse.

The city suffers power outages during an unseasonably hot spell. Nursing-home patients are brought into the ER suffering from hyperthermia. Abby and Pratt disagree on the diagnosis of a fussy baby. Abby falls back to old habits and quickly spirals down to rock bottom on a night she'll forever regret.

Gates and Julia nurture their newfound romance but are soon interrupted by a troubled phone call from Gates' ward, Sarah.

Dr Wexlar is made interim ER chief while staff deals with an industrial accident that leads to a hate crime.

Morning shift begins. The night shift treated 142 patients - a new record. Dr. Morris is confident that by the end of the day the ER can set a new record of 300 patients. Frank reminds him that there has never been more than 250 patients in a day. Dr. Morris bets $300 that they can reach 300 by the end of the shift. Frank, Dr. Gates and Dr. Pratt each bet $100 against him. But will the game be fair? Also, when chaplain Dupree arrives announcing that she's doing a round of the hospital, holding blessing ceremonies and memorials, the guys are against it, except for Dr. Gates, which makes the others suspicious. Frank goes straight to the point. Then there is the accident involving a camel.

Dr. Pratt applies for the job of ER Chief and gets turned down. This causes him to give 2 weeks notice. A female soldier, home 2 weeks from Iraq, is 2 months pregnant and her husband demands an explanation. Neela's cousin has arrived from London for an extended visit and gets pursued by both Dr. Morris and Harold Zelinsky. After 9 years absence, a fall in gym by her son brings Jeanie Boulet back to the ER. Not only is she troubled because of her son, but the disorientation of knowing virtually no one on the current staff does not help.

A firefighter is brought in after being injured at a fire that is blamed on a young girl with genetic problems. Abby decides to prove the girl did not cause the fire. A disfigured man saves his anti-social neighbor. An old woman dies unattended at the ER while the staff are waiting for a psychiatrist. Pratt backs up Abby in an administration meeting. Neela's cousin apparently chooses Harold.

Pratt gets cold feet when Bettina tries to take their relationship to the next level. Neela joins the Ortho's hockey team and is shocked to see who their opponents are in the first game.

Abby deals with her upcoming reunion with Luka in Croatia, a heart transplant patient is admitted when her body rejects the new heart, and a new doctor ruffles feathers.

Neela's marathon shift begins to affect her, and her demeanor isn't helped when she learns the med student she is mentoring is abandoning her specialty.

Abby returns to work; Luka applies for a job elsewhere; the reason behind a brash doctor's being at County is revealed.

A young couple is choppered to County after a car accident, and one of them has a gun. A boy who wants to be a clown is injured in a unicycle mishap, but his father considers him a mathlete and wants him to go to MIT. Pratt visits Bettina in the hospital, but she tells him off.

A young woman with a failing liver has a difficult reunion with her parents, whom she has not seen in six years. Abby receives a job offer. Brenner isn't nice to Laverne after they sleep together.

In the season finale, an ER patient with a mysterious past is afraid that people are trying to kill him. Dr. Moretti returns, trying to make amends for wrecking the marriage of Abby and Luka. Neela makes her way through a difficult M&M conference. Morris treats a woman with lupus who has an attractive daughter.

The ER staff deals with the aftermath of the explosion including a severely injured doctor.

The ER is on guard as Gates gathers the new interns to treat a terrorist, but it's the new doctor and her tough disposition that has everyone on the defensive.

When a gunshot wound victim arrives, the new chief and Abby butt heads on how to treat the patient. Abby comes to Sam's defense when she goes before a nurses disciplinary board.

When a thirteen-year-old gymnast is brought into the hospital after having supposedly fallen off a wall, Dr. Banfield and Dr. Gates must sort out whether abuse is involved.

Patients include an 18-year-old who was stabbed with a fork at his school, and a man shot by a cop at a Halloween party. Meanwhile Sam is annoyed by Gates and Daria.

Both Morris and Neela have authority issues with Dr. Banfield and Gates upsets Sam.

Trying to rescue a three-year-old girl from drowning in a nearby lake, Banfield is reminded of her own experience at County with Dr. Greene caring for her son.

A woman who broke her leg while trying to escape a house fire is brought in with her husband. The husband, Mr. Lotery did not let the paramedics to check him over. Then his brother-in-law arrives, saying that he predicted that something like the house fire would happen - it was actually an arson. Mr. Lotery's brother-in-law becomes aggressive and accuses him of being a pervert, specifically a pedophile. Mr. Lotery denies the accusations. He was sued but found not guilty. When Mr. Lotery is waiting for his wife who's in line for X-ray, he has the chance to calm down a young girl who is afraid of needles. When his brother-in-law sees this, he brutally assaults him, while Dr. Brenner calmly watches nearby... Meanwhile, Neela gets sued for malpractice.

As a snowstorm hits Chicago, Sam's son Alex crashes a car and ends up in critical condition in the ER. Neela gives a deposition in the malpractice suit against her. Dr. Morris and Dr. Banfield are both at a medical conference in Omaha, and when the snow cancels all flights out they share a memorable and surprising evening.

The Last One Before Christmas Break. The one in which Frank and Drs. Sanchez and Wade accidentally get brownies with cannabis in it. The one with the Christmas party. Archie's cousin brings Archie's deceased father's storage container to the ER bay. An injured pregnant Latino woman is brought in. There is something wrong with her baby?. Plus, the Immigration Office wants to deport her.

The police wheel in a casualty of a drug deal-turned-shoot-out. They also bring in an injured woman who was the shooter, plus a pair of wounded brothers who were shot by the man who was shot dead. A 13-year old girl with sickle cell disease is brought in because of abdominal pains; Neela takes her case while Tracy learns from her. Banfield's pregnancy test is negative, which leads to a discussion with her husband and a visit to a specialist.

Neela experiences alternate versions of the same day.

A girl who was hit by a car while riding a bicycle is treated in the ER. When her boyfriend turns up, it seems it may not have been an accident. While a lottery has made millionaires of several nearby convenience store workers, Dr. Banfield and her husband are at the fertilization clinic hoping for their one in a million chance. And as an older woman is brought in assisted by her on-again, off-again husband, three love stories continue in the ER: Dr. Morris meets policewoman Diaz again, Sam discovers that Tony has been seeing Daria, and Neela plays it cool with the returning Dr. Brenner.

An elderly man is brought into the ER after being mugged, and sees things as if it were the 1960s.

A single mother is hurt in a car accident, and must find someone to take care of her daughter. Gates treats a 78-year-old man who refuses surgery that would save his life. Meanwhile Morris's afternoon date with Claudia is not what he expected.

Dr. Carter returns to Chicago and talks Dr. Banfield into allowing him to pick up a number of shifts (without pay). Other happenings include Banfield's dogged pursuit of motherhood, Neela's intensifying personal relationship, and Archie's involvement with a patient who was probably beaten while in police custody - with his new girlfriend the detective standing by.

Banfield and her husband look into adoption, while Carter adjusts to a changed ER. Sam's mother comes into the ER in an altered state of mind.

Carter's illness overtakes him during a critical procedure in a trauma room as a documentary film crew spends the day interviewing the health care givers.

A girl drops off a sick baby at the ER and then leaves; Carter may get a kidney transplant; Gates and Daria care for an elderly woman with multiple sclerosis; Neela and Sam are in Seattle to transport a heart for Joanie Moore, while Doug and Carol are concerned that the donor's grandmother might not consent.

On Neela's last day at County, she has doubts as to whether she is making the right decision.

The ER doctors and nurses help out at Camp Del Corazon, a camp for kids who have had open-heart surgery, working alongside the camp counselor.

As Carter prepares to open a new facility for the underprivileged, some old friends/colleagues gather. Rachel Greene, Mark Greene's daughter, applies for an internship at County.

Kovac and Gates find themselves with a moral dilemma when a woman comes into the ER with acute liver failure; Neela finds herself questioning what is right when Manish decides to give up a kidney to a complete stranger. Meanwhile, Ray fights to get to the bottom of a cheerleader's accidental fall; Abby gets a prediction for her future; and Alex's troubles continue to intrude on Sam's work life.

Gates is assigned to the case of a closeted gay man whose partner clashes with his family; Neela meets her new surgical chief, Dr. Crenshaw; and Pratt must cope with the flood of new interns.

The ER is on guard as Gates gathers the new interns to treat a terrorist, but it's the new doctor and her tough disposition that has everyone on the defensive.

Moretti brings in new attending Skye Wexler to help with the patient load. Morris and Pratt cram for the medical board exam. Gates treats a returning patient from the ICU whose condition has worsen. Sam tends to a teenage girl who is feeling neglected by the staff. Neela's intern, Harold, seeks her advice on a personal matter. Abby struggles with her relapse.

Moretti reassigns Gates back to the ER and treats a couple involved in a car accident. Morris prepares to take his written board exams. Neela is assigned a young genius intern. Kovac plans to extend his stay in Croatia while Abby struggles with single parenthood.

Kovac and Gates deal with a hopeless father whose son succumbs to heart failure; Pratt tries to resolve the tension between him and his brother; an Armenian man tries to be a good samaritan but ends up crashing near the ER; Abby sneaks in baby Joe when she worries his sickness may be worse than it seems; Also, Sam injures the instructor of a self-defense seminar.

As Abby and Luka cope with their newborn's life and death struggle, the couple is shocked to receive a surprise visitor: Abby's mother Maggie. Meanwhile, Sam fears the prospect of criminal charges; Neela discovers that Tony Gates will be joining the ER team as an intern and Morris gets his job back while Weaver gets demoted.

Gates and Julia nurture their newfound romance but are soon interrupted by a troubled phone call from Gates' ward, Sarah.

When Baby Joe is injured by a fall at the playground and rushed to the hospital, Abby is unable to reach Luka to tell him.

Abby deals with her upcoming reunion with Luka in Croatia, a heart transplant patient is admitted when her body rejects the new heart, and a new doctor ruffles feathers.