Screenplay:
Sandro Continenza, Marcello Coscio, Miguel Rubio,Juan Cobos.
Photography:
Francisco Sampere.
Lighting Cameraman:
Francisco Sempere, Enzo Frattari.
Editing:
Vincenzo Tomassi,Domingo Garcia.
Sound Recordist:
Antonio Cardenas.
Sound Editor:
Nick Alexander.
Music:
Giuliano Sorgini.
Production Designer:
Carlo Leva.
Art Director:
Rafael Ferri.
Production Manager:
Felice D'Alisera.
Special Effects:
Luciano Bird.
Special Optical Effects:
Gianetto De Rossi.
Processing Laboratory:
Staco Film, Rome.
Seamstress:
Carmen De La Casa.
Wigs:
Rocchetti & Carboni.
Assistant Director:
Giovanni Arduini.
Continuity Girl:
Eva Del Castillo.
Unit Managers:
Giuliano Principato, Julio Parra.
Producers:
Edmondo Amati(Italy), Manuel P'erez Garc'ia(Spain).
Directer:
Jorg'e Grau (Sola)
Ray lovelock (George)
Christine Galbo (Edna Simon)
Arthur Kennedy (Sergeant McCormick)
Jeannine Mestre (Katie West)
Fernando Hilbeck (Guthrie the Tramp)
Jos'e Ruiz Lifante (Martin West)
Vera Drudi (Mary)
Gencher Gatti (Keith)
Paul Benson (Wood)
Aldo Massasso (Kinsey)
Giorgio Trestini (P.C. Craig)
Roberto Posse (P.C.Benson)
Vincente Vega (Dr Duffield)
Paco Sanz (Mr.Perkins)
Anita Colby (Nurse)
Joaquim Hinjosa (Autopsy Doctor)
Vito Salier (Naked man)
Isobel Mestre (Switchboard Oporator)
Filmed in April 1974 in The Peak District, And in and around Manchester, England. Further filming at Cinecitt'a, Rome and Cinearte Studios Madrid.
Spanish Release: 27 Oct 1975
Italian Release: Oct 1974
U.S. Release: April 1976
U.K. Release: April 1975