In New York, in a mental institution, George Tatum is a psychotic, schizophrenic and amnestic patient that had murdered a family in Brooklyn. He has dreadful nightmares and has been under an experimental treatment for many years by his psychiatrist.
One day, he is considered under control and he is released. He goes to a peep show and immediately he loses control again despite the use of his medication. He drives a car to Florida in the beginning of a crime spree and heads to the house of Susan Temper, a nervous woman left by her husband with three kids. Among them, is the mischievous boy C.J. Temper that likes to play pranks in his family, babysitter and friends.