 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).When his high school crush Susan Andrews (Susan Oliver) is admitted to the hospital after a suicide attempt, Jerome gradually comes to the realization that his problem is a result of his years-long obsession with her.