Margarita is found, naked and bloody in a luxurious house and is promptly taken to a mental institute. The doctors and nurses meant to take care of her aren't exactly who they seem and a mysterious figure, clad in black, circles the premise at night, offing nubile young women.
| Directing | Jesús Franco | Director |
| Writing | Erwin C. Dietrich | Writer |
| Production | Erwin C. Dietrich | Producer |
| Writing | Jesús Franco | Writer |
| Sound | Walter Baumgartner | Music |
| Crew | Peter Baumgartner | Cinematography |
