Dana has big problem on her hands when Susan Jackson comes to the hospital with bruises. Dana wonders if Robert Jackson gave her the bruises because their marriage problems. Dana gets the feeling Susan may not be telling her all she knows.

After Dana learns Robert found his wife at the bottom of the stairs Susan tells that had double vision leading Dana to believe Susan might have Multiple Sclerosis.

Dana takes a leave from the clinic to help her mother through a double mastectomy. Lu's impromptu safe-sex speech at a prep school's career day puts her in the middle of a legal dispute over a date rape. Peter's ""alternative"" approach to pain management for a patient with Hodgkin's disease gets them both arrested. And Dana and Lu must each decide how much they want to know when they are both tested for the mutated BRCA1 and BRCA2 genes that would reveal a predisposition to breast cancer.

A mother- and father-to-be clash over whether or not to allow Dana to perform in utero surgery to correct a birth defect on their unborn son. Lu must decide whether or not to get involved when a woman she was treating for schizophrenia is charged with murder.

It's Christmas at Rittenhouse Hospital. A woman engaged to be married finds out she's pregnant — even though she's a virgin. Robert fires a kitchen employee, assuming her to be drunk on the job. Lu later diagnoses her with Lou Gehrig's disease. Lu's son Marc develops a crush on a runaway teen.

The second season begins with Dana and Lu at odds over the fate of a dead college student's fertilized eggs. The day is further complicated by the arrival of Peter's mother, who clings to the idea that her heterosexual son is gay. Elsewhere, a dying patient and her husband wait impatiently for a donor heart and Nick's appointment to the ER staff is in doubt.

The parents of conjoined twins refuse to have them surgically separated, even though that means they may both die. Lu suspects a leukemia patient may have attempted suicide by starting a fire. Peter is concerned about a patient with a severe rash on her arm and suspects it to be the some kind of virus. Dr. Jackson feels that Rittenhouse needs a good safety & emergency plan and he puts Lana in charge of it.

An Alzheimer's patient attempts to maintain custody of her 15-year-old son with Down syndrome, and a domestic diva puts the health of her unborn child at risk.

Striking nurses send the hospital into chaos, forcing Dana to withhold an experimental treatment for a dying baby. Also, an abused patient of Lu's is turned away.

The Rittenhouse doctors cope with a blood shortage in Philadelphia. Dana helps a patient who unknowingly contracted hepatitis from her husband, and Lu deals with a family of illegal dog fighters who have Lyme disease.

Lu is raped by Rittenhouse's star surgeon — but he insists that the sex was consensual. Meanwhile, Dana attempts to help a critically injured woman whose car crash may or may not have been an accident.