| Assistant Camera | Antonio De Castel Largo, Antonio Minutolo |
| Assistant Director | Franco Lo Cascio |
| Camera Operator | Claudio Morabito |
| Cast | Klaus Kinski (as Dr. Francis Clay), Margaret Lee (as Cheryl Hume), Rosalba Neri (as Anne Palmieri), Jane Garret (as Mara), John Karlsen (as Professor Osterman), Gioia Desideri (as Ruth), Giangiacomo Elia (as The Gardener), Fernando Cerulli (as Augusto), Sandro Rossi (as Policeman), Giulio Baraghini (as Policeman), Ettore Geri (as Inspector), Antonio Radaelli (as Policeman), Monica Strebel (as Nurse Helen), Carla Mancini (as Nurse), Franco Marletta (as Male Nurse), Piero Nistri (as Cheryl's Husband), Daniela Di Bitonto (as Patient), Enzo Spitaleri (as Ruth's Husband), Marco Mariani (as Male Nurse), Gilberto Galimberti (as Policeman), Rosanna Braida (as Patient), Lina Franchi (as Nurse Killed With Scythe (uncredited)) |
| Conductor | Giacomo Simonelli |
| Director | Fernando Di Leo |
| Director Of Photography | Franco Villa |
| Distributor | Florida Cinematografica (as (1971) (Italy) (theatrical) (dubbed)), Miracle Films (as (1972) (UK) (theatrical) (dubbed)), American International Pictures (AIP) (as (1972) (USA) (theatrical) (dubbed)), Hallmark Releasing (as (1973) (USA) (theatrical) (re-release) (dubbed)) |
| Dubbing | C.D.S. |
| Dubbing Collaberation | C.I.D. |
| Film Editor | Amedeo Giomini |
| Filmed At | Elios Film |
| Make-up Artist | Antonio Mura |
| Music | Silvano Spadaccino |
| Music Publisher | Edizioni Nazionalmusic |
| Negative And Positive | Telecolor |
| Prints | Eastmancolor |
| Producer | Tiziano Longo, Armando Novelli |
| Production Company (Presents) | Cineproduzioni Daunia 70 |
| Production Manager | Armando Novelli |
| Production Supervisor | Alberto Longo |
| Set Decoration | Teresa Ferrone, Nicola Tamburo |
| Sound Recording And Editing: English Version | Via Margutta Studios |
| Sound Recordist | Raffaele Benedetti, Romano Pampaloni |
| Sound Registration | Westrex Recording System |
| Unit Manager | Francesco Vitulano |
| Voice Dubbing (English Version) | Carolyn De Fonseca (as (uncredited)) |
| Voice Dubbing: Gioia Desideri | Laura Gianoli (as (uncredited)) |
| Voice Dubbing: Jane Garret | Mirella Pace (as (uncredited)) |
| Voice Dubbing: John Karlsen | Dario Penne (as (uncredited)) |
| Voice Dubbing: Klaus Kinski | Giorgio Piazza (as (uncredited)) |
| Voice Dubbing: Margaret Lee | Gabriella Genta (as (uncredited)) |
| Voice Dubbing: Piero Nistri | Alessandro Iovino (as (uncredited)) |
| Voice Dubbing: Rosalba Neri | Noemi Gifuni (as (uncredited)) |
| Wardrobe | Marcella Moretti |
| Writer (Screenplay) | Fernando Di Leo, Nino Latino |
| Writer (Story) | Fernando Di Leo, Nino Latino |
| Links | https://www.imdb.com/title/tt0066827/?ref_=nv_sr_srsg_0 |
