Klaus Kinski
Dr. Francis Clay
Rosalba Neri
Anne Palmieri
Jane Garret
Mara
Margaret Lee
Cheryl Hume
John Karlsen
Professor Osterman
Gioia Desideri
Ruth
Giangiacomo Elia
The Gardener (as John Ely)
Monica Strebel
Nurse Helen
Fernando Cerulli
Chaffeur
Giulio Baraghini
Policeman
Sandro Rossi
Policeman
Ettore Geri
Inspector
Antonio Radaelli
Policeman
Carla Mancini
Nurse
Franco Marletta
Male Nurse
Piero Nistri
Cheryl's Husband
Daniela Di Bitonto
Patient
Enzo Spitaleri
Ruth's Husband
Marco Mariani
Male Nurse
Gilberto Galimberti
Policeman
Rosanna Braida
Patient
Lina Franchi
Nurse Killed with Scythe (uncredited)