The pilot for the popular TV series is set during 24 frantic hours in the lives of a group of doctors, nurses, and staff members of a busy emergency room at a Chicago hospital. They deal with the seemingly endless casualties that stumble into their place of employment. The central characters are the chief resident and family man Dr. Mark Greene, who is considering a job in private practice due to pressure from his demanding law student wife Jennifer; outgoing Dr. Doug Ross, who deals with cases in his own personal way; straight-arrow Dr. Susan Lewis, trying to get by another long 36-hour shift; inexperienced third-year med student John Carter; cocky surgical resident Dr. Peter Benton; and troubled chief nurse Carol Hathaway.

Benton is called out of surgery to find his senile mother.

It's a day of birthdays. Peter Benton's mother is celebrating a birthday and he tries desperately to find someone to cover his shift. He makes a choice however when Dr. Hicks suggests that he's been absent too often and may wish to consider a leave of absence until his mother's situation is resolved. Carter thinks it's Benton birthday and has a surprise for him. Mark Greene's daughter is also having a birthday but he misses that due to an emergency at the hospital. An elderly, solitary man in the final stages of cancer arrives in the ER on his birthday. Carol Hathaway suggests to her fiancé that they adopt little Tatiana, the AIDS patient abandoned in the ER. Ross has to deal with a young child who was kicked out of a window.

Benton has to attend a banquet at Vucelich's home and asks Jeanie to go with him. Mark hesitates to tell Rachel about the divorce.

It's his day off, but Mark shows up for work anyway. After a patient dies and Morgenstern wants to speak to him, Mark soon regrets coming in after all.

Rumour has it there's something going on between Mark and Susan while Benton questions Vucelich's study and confronts him.

Benton dismisses a patient he hasn't seen who should have been admitted. Carter competes with Dale, a new surgical resident-in-training who once slept with Harper.

Encouraged by Carol, Mark finally asks Susan out. Benton tries to save a boy, despite the fact Doug thinks he's brain dead.

Carol has to fire two of the nurses. Meanwhile, Gant feels Benton is too hard on him.

Carol will hear whether her suspension is permanent or not. Mark and Doyle do what they can to get a patient with Down syndrome on a heart transplant list.

Carol would like to have a women's and children's health care clinic within the ER. Benton has trouble combining work and fatherhood.

Benton has a very extraordinary and interesting case when he comes across a boy with reversed internal organs.

To save rent money, Carter lives in a medical student dormitory as a resident advisor. While visiting Corday at her apartment, Benton meets her father.

Carter and Weaver become unlikely roommates. Lucy is having problems with Carter, and Greene picks up on their squabbling. Corday works long shifts which leads to her exhaustion and a critical medical error, causing a rift with Dr. Anspaugh and problems for Benton. Greene has unpleasant flashbacks when he's hazed by the well-meaning paramedics. Jeanie worries when she and Doug treat a young boy whose childlike mother clearly depends on his 6-year sister to make all decisions. Kerry rediscovers her joy of practicing medicine and decides not to pursue the open ER Chief job, which goes instead to a Dr. Amanda Lee.

Carter and Lucy are discovered and the staff struggles to save them and go on with normal patient care.