After Karen begins having seizures, Aaron discovers that she is terminally ill from the multiple brain metastases of a melanoma; Jeffrey resents having to perform surgery on a mobster about to enter the witness protection program; when the residents attempt to pull a practical joke on Jeffrey, they unwittingly provide comfort to a dying Karen.

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.

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.