Pratt and Chen's lives hang in the balance after a dramatic car chase culminates with them crashing into the Chicago river - and the race to save them begins as they are trapped underwater
Carter struggles to deal with his emotions in the wake of his girlfriend's departure, and Abby treats an injured young woman who was kidnapped from Mexico and forced into sexual slavery
It's a busy Fourth of July weekend for the staff at Chicago's County General Hospital, as Carter oversees an understaffed and overstretched ward, while Ray is upset with Abby
Corday faces disciplinary action over the organ transplant she performed on an HIV-positive patient, forcing her to reconsider her position at the hospital. Meanwhile, Sam faces moving in with Kovac.
Ray makes the mistake of donating a patient's organs without the family's consent. Meanwhile, Carter pursues social worker Wendall and Pratt turns patient processing into a competition.
The action from the emergency room takes place in real-time, as Kovac, Abby and Sam struggle to save the life of alcoholic Charlie (guest star Ray Liotta)
A woman who has been brutally attacked is admitted to the emergency room, and Sam and Kovac take a risk in order to help her communicate with the police
The 15-year-old son of a police officer is faced with a tough decision when his father is admitted to the emergency room with a potentially fatal gunshot wound.
The yuletide season brings its own set of challenges for the emergency room, as the staff scramble to finish work so they can go home for Christmas
Irritated by Lewis's management style, Abby walks out to the ambulance bay to cool off. But a gang who are lying in wait kidnap her and force her to treat another gang member.
A personal injury lawyer capitalises on the ER's floundering reputation by setting up stall directly outside. Meanwhile, Abby returns to work, but is it too soon?
When a girl is admitted complaining of dizzy spells after a kidney transplant, Carter traces the problem to a new drug one of his former med students recommended
While examining a young boy, Pratt finds a suspicious gash across his chest and calls Wendall (Mädchen Amick) for a consultation. Jake tries to convince Abby to date him.
Weaver is shocked when a patient who's been admitted to the emergency room claims to be her birth mother. Meanwhile, Carter confronts a painkiller addict.
Cynthia Nixon guest stars as young mother of three, who is brought in with symptoms of a potentially fatal stroke. Meanwhile, Neela and Ray deal with three children who seem to have been neglected.
In Iraq, a young girl is wounded in a car bombing, and local hospitals are unable to help. Michael Gallant enlists Neela's support to secure the necessary treatment.
Neela is surprised when she hears that Gallant came to ER with a young Iraqi burn victim, while Sam is troubled by a visit from her ex-husband. Pratt treats a child who carries a gun.
A woman suffering from the effects of her hunger strike is brought in to County General, but the doctors are unable to treat her as long as she refuses their help
Carter is accused of murdering the wife of 85-year-old patient Jules - 10 years previously. Meanwhile, Dr Pratt makes a date with a social worker.
Dr Morris has been appointed the new chief resident and immediately locks horns with Dr Pratt as they deal with the casualties from a fire. Meanwhile, Lewis is frustrated when she misses tenure.
Pratt is furious with Neela for performing a complicated procedure on a baby, Ray's procedural error on a stab victim has terrible results, and Abby makes a wrong diagnosis
The staff throw a surprise leaving party for Carter down at Ike's, leaving an inexperienced skeleton crew in charge of the ER. Danny Glover guest stars as Pratt's father.