A poisonous gas is released in a bank and the doctors try to contain the gas, that is threatening many lives including Dr. Hancock.

A cardiologist in NASA's Doctors in space program has a heart attack and Kate takes the doctors place in the program. Dr. Shutt has a patient who needs to tell his father, an Orthodox Rabbi, that he is gay.

Hancock accuses Watters and Austin of racism when they refuse to operate on a black patient. One of Shutt's patients commits suicide when the medicine needed isn't covered by insurance.

Grad accuses a mother are starving her infant to death. Shutt and Catera disagree over a neurological patient. Austin announces her plans with NASA, and Watters taked away her status as Chief of Surgery. Yeats uses his ""sixth sense"" to diagnose a patient.

The hospital prepares for the Doctor of the Year party, and several old friends drop by. Watters goes into a virus-induced coma and gets some words of wisdom from Alan Birch. Camille Shutt returns for the party and Aaron discovers he still has feeling for her. Dr. Nyland returns to the hospital and reveals that he has really changed his life. Geiger also visits the hospital.

Kate discovers that a patient is using Viagra to cheat on his wife; Jack gives a blood transfusion even though it's against the patient's Jehovah's Witness religion; a musician fears his creativity may be stifled by the medicine Aaron prescribes for his bipolar disorder; Joe's son drives the staff crazy as he roams the hospital behaving exactly like his father.

Gordan teaches Kate how to fly. Hancock accuses a police officer of shooting a homeless African-American.

A celebrity dies and news crews invade the hospital to cover the story.

Billy's mother shows up at the hospital and announces she is about to give birth. The star of the road company version on ""Jesus Christ Superstar"" comes to the hospital when the star is ill. Yeats former teacher comes to the hospital with chest pains.

Wilkes must face the parents of a child brought into the ER when it becomes clear that Raymond was responsible for the child's injury. NASA starts interview Kate's colleagues. One of Aaron's patients is attracted to him.

A member of Jack's basketball team sustains a near-fatal injury during a game; Bobby disagrees about the need for his patient to have heart surgery.

Aaron struggles with the loss of a patient; Billy is attracted to Emily's babysitter; a couple asks Bobby and Dennis for help in creating a baby with a genius I.Q.; Joe tries to decide who should go into the hospital's fallout shelter in an emergency.

Kate discovers that she has developed an ovarian cyst which could destroy her plans with NASA. After Kate hears this news she agrees to go to a retreat... that Yeats is leading.

During surgery to resolve an HIV-positive woman's post-partum complications, Diane accidentally cuts herself and is exposed to the virus; problems arise between Jack and Lisa when he discovers that she's been seeing Robert; a homeless man takes shelter in the hospital's main entrance; an unidentified man is hit by a train after trying to save a child; Jack takes up golf in the hospital.

McNeil performs a hand transplant on the patient, and uses the patient's dead mother's hand. Kate is accepted by NASA. An old childhood friends visits Watters and asks for one of his kidneys.

Jack returns after his brother's death; fearing the impact of HMOs on his practice, Joe begins to sell doorway products; Billy's friend comes to the hospital for a heart transplant, and ends up getting an experimental procedure after the hospital receives the wrong organ.

Billy ponders euthanasia when Gordy is diagnosed with rheumatoid arthritis; Lisa tries to help a woman with metastatic breast cancer get into an experimental group even though the woman doesn't fit the study parameters; Aaron's patient confesses to murder.

Kate confronts a world renowned surgeon who's harassed her in the past; Diane's patient has a flesh-eating bacterial infection.

Diane tries to help grieving parents when their three year old child dies; Aaron is institutionalized after an experiment backfires.

A mother gives birth to twins, one black and one white. Kate is threatened with a lawsuit after making a rude comment.

Dr. Hancock's patient, who was using fertility drugs, gives birth to 8 babies.

Kate meets up with an old boyfriend, who turns out to be an ex-husband. Lisa tried to prolong the like of a pregnant woman with brain cancer. Cacaci forces Aaron to investigate his charge that Phillip had an affair with a patient.

The E.R. is flooded with teenagers poisoned by an unknown rave drug; Kate and Sara are hit by a drunk driver; Phillip's fate is decided.

Aaron consults Dr. Gina Simon, a pediatric neurosurgeon after being presented with a 9-week old baby suffering from seizures. Jeffrey Geiger returns to the hospital and promptly fires half the staff, whom then sue to get their jobs back.

A priest is genitally mutilated during a mugging; a patient dies after a routine liposuction; Jeffrey refuses to perform surgery on a child.

A heart becomes available for transplant, but there are two patients waiting and Drs. Geiger and Watters must choose which patient will receive the heart. Jeffrey tries to place Alicia into an exclusive kindergarten. Aaron tries to hold a welcoming party for the new doctors.

A doctor with Tourette's Syndrome is brought to Chicago Hope to operate on an infant with a severe heart defect. A patient comes into the ER with, what he claims to be, Albert Einstein's brain and gives it to Dr. Wilkes. A woman is using plastic surgery to make herself look like a Barbie Doll.

Dr. McNeil goes to magnificent lengths to save the arm of a young baseball star. A little girl is brought into the ER after being hit by a car.

The doctors fight to save Cacaci's life after he jumps from a six story building in a suicide attempt, although Cacaci's fiancee says that someone pushed him off the building.

A widow wants to be impregnated with the sperm of her former husband. Rats take over the hospital.

The hospital is quarantined after a deadly virus is discovered; a child is missing in the hospital.

Dr. Alberghetti performs a surgery with another surgeon, who is in Sri Lanka.

On the way to a football game, Aaron and Jack get sidetracked... after they find themselves in a hostage situation with 3 wounded patients, a loose gunman, and the police about ready to enter the building.

Dr. Hanlon must fight against her department heads when they decide they no longer want her to perform pro-bono operations. Dr. Alberghetti tries to help a young man with a staph infection.

Gina operates on a surgeon who's been diagnosed with Parkinson's disease.

A hepatitis scare forces Dr. Geiger to call for outside help; Dr. Simon's misdiagnosis causes her to doubt herself.

A teenager is forced to live his life as a girl after the slip of a knife, and McNeil goes to court to try to help.

A father is told he can only donate his liver to one of his children, after both go into liver failure. Rose Webber comes back to Chicago Hope and finds that Aaron has started a new relationship -- with Gina.

Keith discovers a heart murmer while giving Alicia a physical. Jeremy performs an appendectomy on Siamese twins.

A mentally challenged couple enters the hospital. The husband needs open heart surgery. The wife discovers that she can't become pregnant after she was sterilized without her consent.

Shutt and Simon invent a procedure and use it to save the life of a girl. McNeil treat a wrestler who's been using steroids.

McNeil's friend is shot. Pancreatic cancer effects one of the conjoined twins that have entered the hospital.

The hospital is purchased by an HMO, and immediately suffers budget cuts. During an operation that Miller is filming for a documentary, the heart stops beating on both the patient and her unborn child.

McNeil goes against procedure and red tape and performs a hip replacement surgery. Shutt and Simon transplant a computer into a patients brain. Alberghetti tries to ignore her feelings for Miller.

Shutt's patient wakes up after being in a coma after 15 years. A man is denied health coverage, after saving Miller's life.

Rumors fly that the hospital is about to be sold again; a man seriously injured in an accident wants to be the guinea pig for the computer program he's invented that can help him move again.