Richard Whorf Director John Hodiak Manuel Cortez Actor Sylvia Sidney Cecily Harrington Actor Ann Richards Mavis Wilson Actor John Howard Nigel Lawrence Actor Isobel Elsom Auntie Loo-Loo Actor Frederick Worlock Inspector Hobday Actor Ernest Cossart Billings Actor Philip Tonge Dr. Gribble Actor Anita Sharp-Bolster Ethel Actor Billy Bevan Taxi Driver Actor James J. Geller Producer Philip MacDonald Screenwriter Tony Gaudio Cinematographer Fred Allen Film Editing Hans J. Salter Original Music Perry Smith Art Director Armor Marlowe Set Decoration Michael Woulfe Costume Design