A woman is fatally stabbed in bed, a prostitute is battered into oblivion and a female painter is strangled with a telephone cord. Another woman, Giulia, who is on her honeymoon, is attacked in a train carriage but the killer flees when her husband Mario comes to the rescue. In spite of his protestations to the police, Mario is accused of being the murderer. He sets out to prove his innocence by conducting his own enquiries. In the meanwhile, a woman in an insane asylum is drowned in a bath and another female victim is power-drilled to death…