In this American mystery film a town is terrorized by a series of murders by "The Bat". He is described as a man with no face who kills with a steel claw hand. The house of a famous mystery writer Cornelia Van Gorder (Agnes Moorehead) takes center stage as it is thought to be the hiding place of a million dollars. "The Bat" attempts to find the money before a murderous Dr. Malcolm Wells (Vincent Price) and others get a chance. It is the fourth film adaption based on a 1908 novel The Circular Staircase.