"A child conceived by a mute servant girl transforms from an innocent youth to a killer beast at night with uncontrollable urges."
Oliver Reed
as Leon Corledo
Clifford Evans
as Don Alfredo Corledo
Yvonne Romain
as The Mute Servant
Hira Talfrey
as Teresa
Catherine Feller
as Cristina Fernando
Anthony Dawson
as The Marques Siniestro
Josephine Llewellyn
as The Marquesa
Richard Wordsworth
as The Beggar
Justin Walters
as Young Leon
John Gabriel
as The Priest
Warren Mitchell
as Pepe Valiente
Anne Blake
as Rosa Valiente
George Woodbridge
as Dominique
Michael Ripper
as Old Soak
Ewen Solon
as Don Fernando
Peter Sallis
as Don Enrique
Martin Matthews
as Jose
David Conville
as Rico Gomez
Denis Shaw
as Gaoler
Charles Lamb
as Chef
Serafina Di Leo
as Senora Zumara
Sheila Brennan
as Vera
Joy Webster
as Isabel
Renny Lister
as Yvonne
Loraine Carvana
as The Mute as a Young Girl (uncredited)
Desmond Llewelyn
as 1st Footman (uncredited)
Rodney Burke
as 1st Customer (uncredited)
John Bennett
as Policeman (uncredited)
Francis de Wolff
as Bearded Customer (uncredited)
Terence Fisher
Director
Anthony Hinds
Producer
Michael Carreras
Executive Producer
Benjamin Frankel
Original Music Composer
Arthur Grant
Director of Photography
Alfred Cox
Editor
Bernard Robinson
Production Design
Anthony Nelson Keys
Associate Producer
Screenplay
Guy Endore
Novel
Roy Ashton
Makeup Artist
Clifford Parkes
Production Manager
Don Mingaye
Art Direction