Season 4

Gang warfare breaks out in the E.R.; Kate refuses to perform a heart transplant; Billy and Diane get back together.

A woman may be making her daughter sick purposely. Kronk wants a child. Shutt's patient dies, and McNeil joins gamblers anonymous.

Dr. Shutt views his life as a musical after he collapses from an aneurism.

Dr. Kronk must decide whether or not to grant the request of a convicted child molester who wants to be castrated. Dr. Shutt struggles to regain his health after his aneurism. McNeil refuses an ""easy cure"" to a heroin addict, and Dr. Grad treats an HIV positive 14-year-old.

Dr. Shutt may have brain damage after his aneurism, so a new neurosurgeon, Dr. Lisa Catera, is brought into the hospital. Dr. Austin gets trapped on an elevator with a sexy electrician.

Kate suspects that the parents of a boy who needs a liver transplant may have pressured his sister, who has cystic fibrosis, into being his donor; Diane learns that she's pregnant; Billy announces that he's going to South America; Aaron tries biofeedback.

Hancock and the police search trash bins for a newborn; male rape; Drs. Kronk and Grad wed at the airport. A basketball player has a heart defect.

Austin and NcNeil fly to London for a conference and are forced to perform lifesaving surgery with only an airline medical kit. Shutt begins his psychiatric residency.

McNeil offers his cabin to Drs. Austin, Catera, and Grad, whom each want to get away from the city for a while. While at the cabin they receive a visit from an unexpected and deadly visitor.

Shutt has his first group counseling session with a family, and tries to help a young man whose brother commited suicide. Wilkes father comes back into his life. Hancock and McNeil try to treat a boy whom he suspects is abused, even though the child and his father deny the abuse.

After a little too much holiday cheer Wilkes is charged with a DUI and must serve a community service in Dr. Hancock's clinic. Watters discovers that his accountant has left the country with Watters money. Shutt turns over a patient to Catera, and the two clash over whether she should perform a dangerous surgery on the patient. Dr. McNeil is elected to play Santa and is a huge hit in the childrens ward. Grad receives her Christmas present a little early.

Austin operates on a pregnant patient with a damaged heart and learns that she had taken the controversial diet pill Phen-phen. An accident reunites Watters and an old flame, the woman he had an affair with. Shutt has his first breakthrough. McNeil and Catera grow closer.

The hospital loses electricity in the dead of winter. Austin must do emergency surgery on a close friend. Pregnant, Grad feels unattractive.

Watters is confined to a wheelchair after a basketball injury and witnesses a murder. Austin receives a bird from Danny, the electrician she's been dating, which causes havoc in the hospital. Diane believes she has found her birthmother.

Catera must operate on a 5-year-old who is suddenly stricken with seizures. An HIV-postive friend of Dr. Grad's talks to Diane about getting pregnant (she wants advice) and Diane (who discovered a lump in her breast) is afraid that neither of them will see their children grow up. A mother and daughter come into the ER handcuffed together.

Catera and McNeil cross roads when her facination with his brother becomes personal. Billy begins to feel ""in over his head"" with the impending birth of his child, so at a desperate attempt at freedom he becomes involved in a bar fight. Austin introduces Danny to her daughter. Watters moonlights as a stand-up comic.

A family eats poisonous mushrooms and the mother and two sons must receive a liver transplant. A donor is found for the mother and the father is a match for the two sons. The father decides to have a live donor transplant, but is told by Kronk that only one of his children can receive the organ. Austin and Cacaci have to attend a sensitivity seminar, which only makes Austin worse. With Shutt's help a patient remembers a sexual abuse that happened during childhood, but the parent vehemently deny it ever happening. Drs. Grad and Kronk get kicked out of lamaze class.

Dr. McNeil attends a medical convention in Las Vegas, believing he can control his gambling addiction. After the son of a close friend dies, McNeil begins gambling again. Watters, Shutt, and Wilkes are forced to share a room in the hotel, when it is overbooked for the convention.

After the mysterious death of a seemingly healthy 15 year-old Dr. Wilkes decides to investigate. A lesbian wants her lover to die with dignity and fights her family to get her wishes.

Diane goes into labor unexpectedly and when no one can find Billy she reluctantly asks Kate to be her coach. Wilkes must get a family to safety from an abusive husband/father. McNeil and Catera take dance lessons (with special guest star Kenny Ortega, who choreographed ""Brain Salad Surgery."" Billy arrives at the hospital and discovers that Diane is having a c-section after her and the baby have gone into distress during the labor.

Dr. Watters' son is found dead in his apartment and Phillip must except the fact that he committed suicide. Dr. Austin brings her daughter to the hospital and she becomes fascinated with the blood and guts aspects of her mother's work. Dr. Catera becomes uncomfortable with Dr. McNeil's romantic pursuits, until she watches one of her patients (who is in much the same situation.)

A famous artist has an inoperable brain tumor. She convinces Dr. Shutt to run away to California with her.

Dr. Kronk's mother visits. Aaron spends time with Samara in California. A woman offers Dr. Hancock money to sterilize some of his patients.

As Dr. Wilkes takes his son to school gunfire errupts. The victims are brought to Chicago Hope and Wilkes finds himself having to deal with his sons post-tramatic distress. Kronk also finds himself viewing the situation in a new light, due to the recent arrival of his daughter. The situation also brings back memories of his son to Dr. Watters. Catera had to operate on the shooter, and feels conflicting emotions. Dr. McNeil pops the question to Dr. Catera. Austin is still turmoiled over the incident at the cabin.