Jerome Littlefield (Jerry Lewis) is an orderly at the Whitestone Sanatorium and Hospital who suffers from "neurotic identification empathy"—a psychosomatic problem that causes him to suffer the symptoms of others and interferes with his ability to function effectively on the job. His unwitting propensity for slapstick-style mayhem sorely tries the patience of Dr. Howard (Glenda Farrell) and Nurse Higgins (Kathleen Freeman).