Deranged surgeon, Dr. Gogol, pines for actress Yvonne Orlac who is planning a break from acting to tour with her pianist husband, Stephen. After an accident mangles Stephen's hands, Gogol replaces them with the hands of a dead knife-wielding murderer which appear to have retained the urge to use knives as weapons. Based on the novel "Les Mains D'Orlac" by Maurice Renard.