 | John Saxon als Dr. Marcello Bassi |
 | Letícia Román als Nora Davis |
 | Valentina Cortese als Laura Craven-Torrani |
 | Dante DiPaolo als Andrea Landini |
 | Titti Tomaino als Inspector |
| Luigi Bonos als Albergo Stelletta |
 | Milo Quesada als De Vico / Paccini |
 | Gustavo De Nardo als Dr. Facchetti |
 | Giovanni Di Benedetto als Professor Torrani |
| Jim Dolen als Priest (uncredited) |
 | Franco Ressel als Arresting Officer at Airport (uncredited) |
| Robert Buchanan als Dr Alessi |
| Marta Melocco als Murder Victim |
 | Lucia Modugno als Nurse |
 | Franco Moruzzi als Policeman |
| Virginia Doro als Torrani's Maid |
 | Mario Bava als Uncle Augusto |
| Chana Coubert als Ethel Windell Batocci |
 | Adriana Facchetti als Woman in Sguattera Restaurant |
| Dafydd Havard |
 | Tiberio Murgia |
| Peggy Nathan |
| Lido Pini |
 | John Stacy |
| Mario Bava | Director of Photography |
| Mario Bava | Director |
| Roberto Nicolosi | Original Music Composer |
| Mario Serandrei | Editor |
| Mara Rocchetti | Hair Designer |
| Euclide Santoli | Makeup Artist |
| Eliana De Sabata | Screenplay |
| Mino Guerrini | Screenplay |
| Paolo Mercuri | Production Manager |
| Antonio Rinaldi | Gaffer |
| Ennio De Concini | Story |
| Enrico Checchi | Second Assistant Director |
| Ennio De Concini | Screenplay |
| Sergio Corbucci | Screenplay |
| Neda Matteucci | Script Supervisor |
| Mario Bava | Screenplay |
| Salvatore Billitteri | Associate Producer |
| Giorgio Giovannini | Art Direction |
| Ubaldo Terzano | Camera Operator |
| Luigi D'Andria | Set Decoration |
| Tina Grani | Costume Design |
| Lina Caterini | Assistant Editor |
| Sergio Corbucci | Story |
| Eliana De Sabata | Story |
| Massimo De Rita | Executive Producer |
| Franco Prosperi | Assistant Director |
| Armando Govoni | Production Assistant |
| Franco Prosperi | Screenplay |
| Emilio Schuberth | Set Dresser |
