 Paul Farell (Kerwin Mathews), a worthless drifter down on his luck, becomes entangled with Eve Beynat (Nadia Gray) and her daughter Annette (Lilliane Brousse), who run a small hotel in Southern France. Georges Beynat, Eve s husband, has been in an insane asylum for the past four years for blow-torching to death a man who raped his daughter, Annette. At first, Paul is interested in Annette, but Eve easily manipulates Paul into helping her husband Georges escape from the insane asylum by pretending that she loves Paul and wants to go away with him. With Paul and Eve s help, Georges escapes, but instead of leaving the country as he had promised, the killings soon start again, with a blowtorch invariably used as the murder weapon. As Inspector Etienne (George Pastell) becomes suspicious, we discover that the man who escaped is not Georges Beynat at all, but rather Henri (Donald Houston), a male nurse at the asylum, who has fallen in love with Eve Beynat during her visits to her husband. Henri has killed Georges Beynat, and now plans to kill Annette, who has discovered the deception. Eve lures Annette to a rock quarry, where Henri waits for her.