John Carradine stars as Dr. Charles Randolph, a scientist dedicated to deciphering the secrets of life and death. Aided by assistant David Cochran (Robert Shayne), Charles conducts experiments that have horrifying side effects. Charles's lonely wife, Elaine (Claudia Drake), is frightened by his work, and in order to protect her, housekeeper Maria (Rosa Rey) unleashes a torrent of voodoo that wrecks havoc.