Pratt's car crashes into the river. Chen and Pratt's injuries are bad, but they're not as bad as Elgin's--he dies. Abby begins her internship at County, as do Ray Barnett and Howard Ritzke. Alex and Sam crash at a motel, where Alex places a collect call to Luka. Luka comes to find them and asks Sam to return to Chicago with him. The Lopez family gives Weaver full custody of Henry, and will take care of him while Weaver is at work. Carter and Kem scatter their son's ashes and Kem returns to the Congo.

Carter suffers with insomnia and depression over his separation from Kem, and falls off the wagon. Luka tells Sam he loves her and invites her to move in with him. Neela's parents visit, confused by her choice to drop out of Michigan. The nurses freeze out Abby after a slip of the tongue to Haleh. Weaver advises Barnett to change his appearance. Abby treats a "damaged girl", a young Mexican woman kidnapped and forced into sexual slavery.

It's a busy 4th of July. Sporting a large scar on his head, Pratt is back at work, although Carter sends him home early. Neela looks for employment without much success before taking a job far below her expectations. Abby and Ray argue on the course of treatment of an altered bicycle messenger. The new OR attending, Dr. Dubenko, declines to perform an illegal organ donation procedure between two HIV+ people. However, Carter convinces Corday to perform the operation. Luka takes Alex to his soccer game, although Alex isn't looking for a replacement for Steve. Susan, Chuck and baby Cosmo visit. New resident Howard may be obsessive compulsive.

Two small children are rushed to the ER after falling from a third story window, allegedly escaping their mother's violent, abusive ex-husband; however, additional facts reveal a different cause. Susan becomes Chief of Emergency Medicine. Plagued by his OCD, Howard abruptly quits his residency, leaving a slot open. Susan can't find anybody to fill the position, so offers Neela an ER internship. Corday is in trouble after her illegal organ donation procedure, facing dismissal and loss of license. Weaver offers her a non-tenured position as a clinical instructor, but Corday decides instead to quit and return to England.

It is Neela's first day back at the ER and Pratt orders each intern to discharge 25 patients by the end of their shift, tracking their output. Neela struggles with frustration as she trails in the competition and is asked rude personal questions by a medical student Jane Figler while trying to help a patient with severe leukemia. Ray leads by a landslide, but makes a major mistake by green-lighting organ donation against the family's wishes after he sped through the paperwork. Not interested in the competition, Abby fakes a needle prick in order to get HIV-protective medication for a worried patient- and deals with a med student who is smitten for her. Dubenko looks out for Abby when Ray rides all over her in a trauma. Dubenko is also a little obsessed with physics.

The last 44 minutes of ex-con & alcoholic Charlie Metcalf's life are in the ER, as he slowly succumbs to end-stage liver failure.

Sam and Luka are moving in together. When a raped and badly beaten woman is brought into the ER, Sam wants to try a risky procedure to let the woman talk. The woman dies, however, and Luka covers for Sam. At Susan's one-month review, Weaver suggests that she be more of a leader. Lewis schedules a JCAHO emergency drill without telling the staff, creating chaos. Even after she gives birth, a young girl insists that she's not pregnant.

Lewis, Neela, and Ray treat a police officer shot during a robbery. His 15-year-old son must make a difficult decision on his father's course of treatment and he turns to Ray for advice. Ray promises to help the boy explain his decision to his mother, but he instead leaves for a gig and later gets an angry earful from Neela after the boy is browbeaten into changing his mind. Abby and Dubenko help a young girl whose mother does not want her to have critical surgery at County, but her condition worsens before her transfer can go through. Luka begins to take a more active role in Alex's life after he's suspended for bringing a copy of Maxim to school. An exhausted Chen returns to work, where Pratt finds her stealing potassium.

It is Christmas Eve in the ER, and the hospital is overrun by homeless. When Chen can't find someone to cover her shift, she quits, leaving Carter as the only ER attending. Carter and an off-duty Ray save a critically injured boy, and Ray learns the real story of his injury from his little sister. Abby and new medical student Jake treat a dialysis patient who is in critical condition, but she can't reach his physician, who is supposed to be on call. With encouragement from Carter and Dubenko, she breaks the rules to save the patient's life. Pratt heads to Chen's house and finds she is about to euthanize her father, who has begged her to do so in his lucid moments, and then take his body back to China.

While on a smoke break, Abby is kidnapped by two young gang members, who want her to fix a wounded friend. Frustrated with her subordinates not listening to her, Susan faces the fact that she can't be everyone's friend and their boss at the same time. Neela is having trouble relating to her patients.

Lewis assigns Kovač to teach the residents how to communicate more effectively with their patients. Pratt continues to dazzle with his medical skills but struggles with his teaching role. Luka and Sam argue all day. Abby tells Neela that she needs to find a new living arrangement. After finding out that Ray's roommate backed out on him, Neela decides to share an apartment with Ray. Following another day of Luka's guidance, Neela develops a crush on him. It's Abby's first day back at work since her abduction but it may be too soon for her to return. Lawyer Herb Spivak returns to the ER, trolling for clients and being thrown out numerous times.

Carter treats a 16-year-old girl who is suffering kidney failure after taking a new drug to control her seizures. The girl's urologist, the person who recommended the drug, is a former med student of Carter's. Everyone knows about Neela's crush on Luka; he tries to pass her off to Carter for the day. After Luka tells Neela that he didn't mean to mislead her, she has a brief talk with Sam about the situation. Abby and Jake work together on a number of sex-related cases. Jake wants to date Abby, but she turns him down because he's her med student.

Kovač and Pratt examine a man who was shot after he confronted his boss with a gun. Kovač and Dubenko disagree about possible internal injuries, leading Kovač to try several procedures to test his theory. Ultimately Kovač is proven correct, while the patient refers to the day as the best of his life. Pratt also treats a boy with a suspicious gash but releases him despite Wendall's objections, with tragic results. Jake tries to convince Abby that they should date and changes shifts with Jane so that Abby is no longer his supervisor.

Weaver is spending the day working in the ER when she meets her birth mother, who has disguised herself as a patient to see Kerry. Her mom is a devout Christian, in town with her choir, and does not understand Weaver's lifestyle "choice". She offers her love, but Weaver just wants acceptance. Jake has been spending every night at Abby's apartment. Abby says it's out of convenience, but Neela thinks otherwise. Jake and Abby have trouble hiding their relationship at work, especially from Weaver.

Ellie Shore is a mother of three who has a stroke and cannot speak. While she is treated, we are inside her head, hearing her thoughts. As Carter and Wendall's relationship deepens, an overnight phone call from Kem reveals its limitations, and Wendall walks away. Neela treats three kids with a suspicious father. Morris has applied for Chief Resident. Luka and Carter want Pratt for the job, but Pratt's not interested in it. Dubenko casually pursues Abby with an offer to co-write an article.

Gallant and Neela have been exchanging letters regularly. Gallant struggles with the war he sees every day, while Neela is searching for her life's purpose. Gallant enlists Neela's help in getting a critically burned Iraqi girl lined up for surgery in Chicago and heads for the U.S. with 72 hours leave.

Neela is surprised when she hears that Gallant came to the ER with the young Iraqi burn victim, but they later connect on a personal level. Sam's ex-husband Steve visits, and desk clerk Frank learns that he has been in prison in Colorado. Steve loots Sam and Kovač's apartment, but Kovač blocks him from leaving with Alex. Pratt treats a child whose gun went off in his pocket and learns that he received the gun from his mother, while being attracted to a young woman who runs an anti-violence program.

Lewis, Neela, and Sam are legally blocked from treating a woman dying from the effects of a hunger strike designed to prevent her son from being deported. Pratt struggles to find a way to convince a woman with breast cancer to seek treatment. Abby treats two elderly sisters involved in a mugging. To Weaver's delight, Carter donates $150 million to the hospital's new venture, in exchange for naming rights. Carter calls Kem and asks her opinion on The Joshua Carter Center, named after their stillborn son.

Mr. Rubadoux, whose wife was a patient of Carter's ten years ago, comes into the ER with heart problems, wanting nothing to do with Carter. Anspaugh and Kayson advise Ruby to have surgery, but Abby tries to get him to consider the risks. Finally, Carter apologizes to Ruby for lying to him about his wife. Pratt asks Olivia from Ceasefire out. When he shows up at her office to pick her up, he's ambushed into speaking at an anti-violence meeting. Lewis does her presentation for tenure, and Sam takes a home pregnancy test. Ray tries to stop the Chadwick sisters from leaving without having been seen by social services. Also, Morris may end up with the chief resident job despite a disastrous presentation.

Carter receives early tenure at Susan's expense. Luka finds Sam's pregnancy test, and asks her the result. They argue all day, Lewis suggests if they can't sort it out they may need therapy. Pratt's friend convinces him to attend an old friend's 30th birthday party. Ray thinks a 14-year-old is a drug seeker, but he's really the victim of molestation. Abby meets Jake's extended family at his niece's baptism. Morris is the new chief resident.

After hearing that Kem's mother is sick, Carter flies to Paris to see Kem. While there, Carter offers to move back to Africa to start all over. Birdie and Rebecca are back; Rebecca was strangled by their niece Shelley, so Birdie stabbed Shelley. Neela, Abby and Ray all make rookie mistakes with various patients. While in counseling, Sam reveals that she thinks that she and Kovač should not be together. Abby makes it clear that she and Jake do not have a future together.

Carter's last day at County General is marked by the "surprise" party being thrown for him. Ray takes charge when a balcony collapses at a party that he's attending. With all of the attendings at Carter's party, he talks Abby into taking 4 trauma patients while the hospital is closed to trauma. Pratt briefly visits his dad. Alex doesn't know his dad is in jail and is upset when Sam won't let him visit him, so he steals her credit cards and hitches a ride out of town.