J.D. (Zach Braff) is accidentally stuck with a needle that was just used to test a patient for Hepatitis B. He's pretty calm considering the fact that he may contract a dangerous disease. The wait for the test results is a long one. During the waiting period he meets four doctors, Dr. Bailey (Ed Begley, Jr.), Dr. Douglas (William Daniels), Dr. Franklin (Stephen Furst), Dr. Lamar (Eric Laneuville), who frighten him with their worst case scenario stories. Even though his test results come back negative, J.D. is still afraid of catching something. He hides from infectious patients.

Meanwhile, Elliot (Sarah Chalke) and Sean's (Scott Foley) relationship is going so far so good. When they're together they think of nothing but having sex. But too much of a good thing is never good. She slowly and reluctantly realizes that she can't handle a relationship and a heavy workload so she breaks up with Sean. Turk (Donald Faison) starts to feel self-conscious about his weight after Carla makes a crack about his ever-expanding stomach. Reluctantly, he enlists Dr. Cox's (John C. McGinley) help in getting back into shape.