Psycho IV: The Beginning delves into the disturbing childhood and twisted mind of Norman Bates, exploring the origins of his psychopathic tendencies. Set years after the events of the original Psycho, Norman's life takes a dark turn as he confronts his troubled past and battles the demons within him.

Marion Crane embezzles money and flees to a remote motel run by Norman Bates, only to be brutally murdered by his psychotic mother. Marion's sister and her boyfriend investigate the mysterious circumstances.

In Psycho III, a mysterious man named Duane checks into Bates Motel, unaware that the motel's owner, Norman Bates, is a psychopath. As Duane becomes entangled in a murder spree, he must confront his own mysterious past and fight for his survival.

Norman Bates, who has been released from a mental institution, continues his murderous ways and terrorizes a small town. As the bodies start piling up, he must try to prove his innocence and find the mysterious murderer.