 | Stephen Forsyth als John Harrington |
 | Dagmar Lassander als Helen Wood |
 | Laura Betti als Mildred Harrington |
 | Jesús Puente als Inspector Russell (as Jesus Puente) |
 | Femi Benussi als Alice Norton |
 | Antonia Mas als Louise |
 | Luciano Pigozzi als Vences (as Alan Collin) |
 | Gérard Tichy als Dr. Kalleway (as Gerard Tichy) |
 | Verónica Llimerá als Betsy Wester (as Veronica Llimera) |
| Pasquale Fortunato als John Harrington as a Boy (as Fortunato Pascuale) |
| Ignasi Abadal als Jimmy Kane (as José Ignacio Abadaz) |
| Silvia Lienas als Vicky |
| Montserrat Riba Vidal als Rosy Miller (as Monserrat Riba) |
 | Susy Andersen als Sdenka (archive footage) (uncredited) |
| Guido Barlocci als Unknown (uncredited) |
| Bruno Boschetti als Policeman (uncredited) |
| Elina De Witt als Model (uncredited) |
 | Rika Dialina als Maria (archive footage) (uncredited) |
 | Boris Karloff als Gorca (archive footage) |
 | Glauco Onorato als Giorgio (archive footage) (uncredited) |
| Mario Bava | Director |
| Mario Bava | Screenplay |
| Mario Bava | Director of Photography |
| Manuel Caño | Producer |
| Soledad López | Editor |
| José María Tresserra | Costume Design |
| Sante Maria Romitelli | Original Music Composer |
| Santiago Moncada | Screenplay |
| Giulia Mafai | Production Design |
| Jaime Deu Casas | Camera Operator |
| Elisa Aspachs | Makeup Artist |
| Pietro Ortolani | Sound |
| Miro Grisanti | Title Designer |
| Graziano Fabiani | Assistant Production Manager |
| Lamberto Bava | Assistant Director |
| Gianna Spirito | Assistant Decorator |
| Marcello Anconetani | Assistant Camera |
| Gianlorenzo Battaglia | Assistant Camera |
| Enzo Ferla | Unit Production Manager |
| Lamberto Bava | Second Unit Director |
| Jesús M. Herrero González | Set Designer |
| Patrizia Zulini | Script Supervisor |
| Jose Adrian | Still Photographer |
| Antonio Angrisano | Production Secretary |
| Giuseppe Parrabano | Still Photographer |
| Emilio Varriano | Camera Operator |
| Marisa Agostini | Script Supervisor |
| Antonio Rinaldi | Director of Photography |
| Mario Bava | Title Designer |
| José Pedro Villanueva | Assistant Production Manager |
| Luigi Biamonte | Title Designer |
| Ricardo Walker | Assistant Director |
| Nadia Fabriani | Set Costumer |
| Laura Betti | Screenplay |
| Enzo Ferla | Production Assistant |
| Hipólita López | Hairstylist |
| Jaime Fernandez | Production Manager |
| Avelino Carla | Assistant Camera |
| Luigi Zito | Conductor |
| Mario Musy Glori | Screenplay |
| Pierantonio Mecacci | Makeup Artist |
| Emilia Zachini | Hairstylist |
| Giuseppe Zaccariello | Producer |
| Giuseppe Aldrovandi | Assistant Art Director |
| Antonio Rinaldi | Camera Operator |
| N.W. Russo | Presenter |
| Mario Bava | Camera Operator |
| Liliana Serra | Assistant Editor |
