Kate returns to Chicago to face possible arrest and her ex-husband, as well as suspension at work. Aaron ponders Philip's bitterness over Aaron's apparent support of Tommy Wilmette. Dennis struggles to regain his health. Dr. Nyland returns to find a new doctor in charge of the trauma service. Kronk and Grad continue to quarrel as he prepares to leave Africa.

Kate cares for her dying father and gets some words of wisdom from Tommy when he brings Sara for a visit; Philip recruits Dr. Jack McNeil to head up orthopedics; Diane returns, only to find that Billy has remained in Africa and that her lab has turned into a storage room; Keith places himself in legal jeopardy when he decides to help an injured drug courier evade arrest; Aaron persuades Tommy to give the hospital six months to turn itself around with Philip at the helm.

Aaron and Jack join forces in operating on a man who sustained multiple fractures in a parachute jumping accident; Diane rejoins the staff as a teaching attending in internal medicine, and quickly draws a demanding and manipulative patient who's making the staff miserable; Kate's grief over her father's death is compounded when she's carjacked on her way home from his funeral and his ashes are not recovered with the car; Diane unsuccessfully seeks some moral support from Dennis and Philip; after Tommy tells her some hard truths about creating her own misery, Kate decides to take responsibility for the choices she's made, and starts by telling Peggy Harrod the truth about her daughter's death; Jack takes one on the chin when he gives the parachutist's would-be bride some bad news; Kate returns home to find the carjacker has returned her father's ashes while burglarizing her home; Philip has it out with Aaron and reaffirms his intention to keep Tommy from closing the hospital.

Dennis and Jack clash over the best mode of treating the arthritic knee of a world class cyclist; Aaron makes a new friend when he takes on a new research assistant; Kate and Danny have their suspensions reviewed by the board; Phillip plunges back into patient care by performing an experimental procedure on a woman who exhibits unusual complications from a liver tumor; Caroline discovers that orthopedics are not for her; Dennis faces an emotional struggle in the aftermath of his shooting.

Kate returns to duty and finds that her reinstatement comes with a cut in title, salary, staff, and office; Jack replaces the hip of an older man who has opinions on everything, including how Jack should live his life; Aaron has mixed emotions when Grace comes up with a much-needed improvement for a surgical shunt he's been developing; Kate is humbled when a young couple whose daughter needs a heart transplant chooses another doctor after they discover her change in status; Tommy thinks it would be a good idea for the hospital to advertise, and hires a publicist who manages to get under everyone's skin as she creates a commercial that ends up looking strangely familiar.

Austin sprays a subpoena server with mace, inspiring his fellow servers to wage war on the hospital. Hancock tries to counsel a woman in her late forties whose health is severely threatened by her pregnancy but who refuses to let the baby be delivered early. Kronk finally returns to Chicago, dressed in Masai garb, and tries to reconnect with Diane.

Aaron faces a huge moral dilemma when he's asked to operate on a death-row inmate scheduled to be executed in two weeks. McNeil treats a feisty old lady whose daughter is an old flame os his. Dr. Watters entertains an amnesiac, believing that he's a distinguished visiting doctor.

Austin's cystic-fibrosis patient is just one of four patients needing transplants who have to wait in fear and hope when a potential donor appears but is prematurely pronounces dead and entered into the donor system by the inexperienced Eggert.

Kronk puts himself and Grad into a difficult position when he treats an old hockey pal who turns up after just being released from jail with a bullet in him. Wilkes and his wife face some basic decisions about their lives when they must decide what sort of neighborhood to move to.

Austin and Underhill both have to face the consequences when they tell the truth. McNeil contemplates surgery to prolong a jockey's career. Kronk lies to a teenage smoker with a cough.

Diane is faced with a dilemna when she has an opportunity to examine a 500-year-old Incan mummy temporarily in town for an exhibition. An accident victim loses his memories but gains a much nicer personality, presenting Shutt and McNeil with a dilemmna.

Wilkes saves a motorist who was attempting suicide. Austin falls for a politician.

A hit-and-run victim escapes serious injury but her infant twins face a desperate crisis. Hancock faces testifying in court against his brother-in-law. Patient Linda Fortin's heart continues to grow weaker as her pregnancy progresses, endangering herself and her baby.

White supremacists on the run following a failed assassanation attempt against the President hole up in a grocery store with an injured member and demand a doctor from Chicago Hope to treat him.

Aaron's practical joker college roommate arrives for a visit and announces that he wants Aaron to marry his widow, Aaron's former girlfriend, when the malignant and inoperable tumor in his brain finally takes his life in a few weeks; Keith and Danny continue to clash; Aaron runs into an old friend as he stumbles home after a night of drinking with his college roommate; Gina has a miscarriage, but a grieving Keith wonders if it wasn't deliberate; Karen suspects that Jack's gambling again, an accusation which he denies; Maricela puts the moves on Aaron; Karen is wary when Jack finally comes to her for help.

An old friend of Austin's asks for help in getting pregnant. A cancer patient needs marijuana for her well being. Shutt's friend returns from Italy without his wife.

Kate flies to Washington with Tommy to speak to Congress about health care. Back in Chicago, her friend Marina makes a decision about adoption. McNeil's patint Harriett Owens is hospitalized again.

Aaron and Phillip announce that they are buying the hospital from Wilmette, although their plans for keping the solvent do not please any of their colleagues. An HMO lawyer obsessed with ""patient responsibilty"" holds the reins on some lucrative coronary-bypass business. A patient with private insurance receives test after test for all of his petty complaints.

Aaron discovers that his late father wasn't his biological parent when he meets the eccentric sculptor who is; Phillip learns something about his estranged son when an emergency arises; Kate treats an 11 year-old genius who hungers for contact with his overwhelmed father.

Kate lobbies for another heart for a prominent author whose first transplanted organ is failing and who also has a continuing heroin addiction. McNeil's gambling problem grows worse. Danny Nyland becomes a patient when he runs into a telephone pole with his car.

Grad tries to persuade a hesitant Kronk to perform a double mastectomy on a healthy woman does not have cancer but who does have the gene for breast cancer and a family history of the illness. Austin struggles to get a reluctant Sara into an exclusive girls school. Nyland returns to work following his accident and throws himself into trying to identify a severely beaten and comatose young woman.

Word of Billy's and Diane's engagement receives a mixed reception at the hospital; Jack returns from vacation with a windfall and a feverish belief he's on a winning streak; Kate alienates some colleagues when a reporter follows her around the hospital; Jack takes on the delicate job of operating on an infant with an exposed spinal cord.

Kate finds herself in a no-win situation when a child is injured during one of Sara's softball games. Phillip's Colonel from Vietnam is admitted with rheumatoid arthritis but refuses treatment. Nyland is suspended again. Shutt get a TV gig.

After a gang member dies in the ER, the boy's mother claims that one of the doctors suggested they ""Let him die"" so a prosecutor calls in Wilkes, Nyland, McNeil and Watters for widely varying statements about what actually happened during the crucial time period.

McNeil doesn't cope well with the demands for attention from Karen, his ""roomate"" and a thereapy patient claiming that McNeil's his father. Billy lears that Aaron kissed Diane, and handles it very badly. A depressed Nyland gets one more unwelcome surprise. Phillip receives an offer from Emma.