It's a busy Fourth of July and Carter is the only attending working.

Carter, Pratt, Kovac and Abby are dealing with a woman and her three children who've jumped from the third floor of an apartment building to escape from the violent husband/father. Meanwhile Dr. Lewis becomes Chief of Emergency Medicine, Howard quits his internship and Dr. Corday is facing dismissal.

Neela starts a new job in the emergency room after working at the convenience store near the hospital. On Neela's first day, Pratt expects the interns, Abby, Ray and Neela, to take on a large patient load during their shifts. Pratt turns processing the patients into a competition, in which Ray is clearly going to be the winner.

An ex con and alcoholic patient, Charlie Metcalf (Ray Liotta) passes out in the waiting room and is brought to the emergency room by the doctors. It shows the real time of 45 minutes with an patient of his life story and his final days in the ER, which touches the doctors treating him.

A wounded police officer's teenage son must make a life or death decision. Abby tries to convince a girl needing appendicitis surgery's parents not to transfer her and do the operation at County, but her father wants her transferred to another hospital due to his own trauma with surgery complications from years before.

Abby has a dialysis patient in critical condition, but she cannot find his physician, who does not want to be bothered during the holidays.

Two teens enter the ER with gunshot wounds. When one dies, Neela botches telling the next of kin, making the woman hysterical.

When a 16-year-old girl who had received a kidney transplant from her father arrives at the emergency room feeling dizzy, Carter traces the problem to a new drug that the girl was taking to control seizures related to her kidney dysfunction.

While examining a young boy, Pratt finds a suspicious gash across his chest and calls Wendall for a consult. Kovac and Pratt examine a man who was shot when he confronted his boss with a gun. Jake tries to convince Abby to date him despite his being her student.

Dr. Weaver meets her birth mother, but their relationship changes when Kerry reveals she is gay. Dr. Carter causes a commotion when he confronts a couple hoping to scam some painkillers.

A soccer mom finds herself completely aware of everything going on around her, but is unable to move or speak after suffering a stroke.

Neela (who's in Chicago) and Gallant (who's in Iraq) miss each other and write letters. Gallant also tries to save the life of a little girl.

Sam's ex-husband shows up and wants to take Alex on a trip. Gallant is back and Neela hopes to see him before he goes back to Iraq.

Jules 'Ruby' Rubadoux is back in the ER. He's still angry with Carter about the death of his wife.

Morris is named the new chief resident, which makes nobody really happy, except Morris. Meanwhile Luka and Sam are having communication problems, Carter gets a promotion Susan really wanted and Ray finds out a 14-year old who always comes in for free drugs has been raped.

Casualties of a disaster flood the ER, which is short-handed because everyone is at Dr. Carter's going-away party because he's leaving the ER after 11 years. Dr. Pratt looks for the courage to confront his father, Charlie.

Luka has a very bad day: New nurse manager Eve Peyton notices he doesn't want to work with Sam and tells him so. At the end of the day he's drunk and Abby takes him home.

The rainy night brings in diverse patients, including a mother involved in a car accident with her baby, a man with a satisfaction facilitator, and a comatose patient who suddenly wakes up. Also, Sam stands up to Eve and her strict ways and Jerry gets struck by lightning.

A new attending, Dr. Victor Clemente, comes aboard and quickly makes a stir in the ER. Abby's breast cancer patient convinces her to take a long awaited test. Luka befriends a young woman who awakes from a six-year coma. Also, Weaver shows Clemente who runs the ER.

Pratt's half-brother tries to get him to make amends with his estranged father. Clemente treats an infant chimpanzee and involves Abby and Neela on the secret case. Eve promotes Sam and her first task is to fire a beloved nurse.

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.

Gallant impulsively asks Neela to marry him that exact day; she says I do but soon gets cold feet. Morris stands up to Weaver on a patient's course of treatment. Luka, Sam and Clemente treat a boy who contracted HIV from his mother. Also, Abby and Luka redefine their relationship and Luka is named the new Chief of Emergency Medicine.

Ray helps an old friend escape from her abusive father. Dubenko volunteers in the ER but can't seem to handle a slow day. Abby and Kovac go baby shopping, while Neela gets unexpected and upsetting news from Gallant.

Dr. Nate Lennox, a former professor with ALS, is brought in as the progression of his disease is chronicled through his own flashbacks as he is treated by each of the doctors at one point. As Lennox wants to give up, Abby fights to convince him to keep on fighting.

An unexpected visitor puts Clemente in the middle of a domestic dispute. Meanwhile, Luka and Abby await test results on their unborn child; Neela struggles with her surgical elective and Pratt ends up with an unexpected suitor when he participates in a charity bachelor auction.

Abby and Luka desperately try to keep a young woman alive who was brought into the ER with stab wounds to the neck. As her condition worsens, Clemente steps in and tries a risky procedure on her to save her life. Meanwhile, Neela pulls an all-nighter preparing to speak at a surgeons' convention; Ray treats a man who claims he has swallowed a bottle of pills; and Sam decides to take a part-time job with Richard to help with childcare expenses.

Pratt struggles to get a straight story when two abused boys come into the ER with their father. Two U.S. Army officers enter the ER.

Weaver, Kovac, and the other doctors work frantically to try to save Jerry and a pregnant Abby, who were both critically injured during the shootout that left the ER in shambles. Meanwhile, Sam tries to escape from her ex-boyfriend and his criminal accomplices as they head north, but things quickly turn violent.

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.

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.

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.

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.

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.

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.

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.

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.

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.

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 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.

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.

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.

Neela experiences alternate versions of the same day.

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

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.

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

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.

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.

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.

Ray helps an old friend escape from her abusive father. Dubenko volunteers in the ER but can't seem to handle a slow day. Abby and Kovac go baby shopping, while Neela gets unexpected and upsetting news from Gallant.

The rainy night brings in diverse patients, including a mother involved in a car accident with her baby, a man with a satisfaction facilitator, and a comatose patient who suddenly wakes up. Also, Sam stands up to Eve and her strict ways and Jerry gets struck by lightning.

While examining a young boy, Pratt finds a suspicious gash across his chest and calls Wendall for a consult. Kovac and Pratt examine a man who was shot when he confronted his boss with a gun. Jake tries to convince Abby to date him despite his being her student.

Neela starts a new job in the emergency room after working at the convenience store near the hospital. On Neela's first day, Pratt expects the interns, Abby, Ray and Neela, to take on a large patient load during their shifts. Pratt turns processing the patients into a competition, in which Ray is clearly going to be the winner.

Abby and Luka desperately try to keep a young woman alive who was brought into the ER with stab wounds to the neck. As her condition worsens, Clemente steps in and tries a risky procedure on her to save her life. Meanwhile, Neela pulls an all-nighter preparing to speak at a surgeons' convention; Ray treats a man who claims he has swallowed a bottle of pills; and Sam decides to take a part-time job with Richard to help with childcare expenses.

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.

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