"Insurance agent-physician collects on policies of men murdered by a disfigured resident of the home for the blind where he acts as doctor-on-call."
Bela Lugosi
as Dr. Feodor Orloff / Prof. John Dearborn
Hugh Williams
as Det. Insp. Larry Holt
Greta Gynt
as Diana Stuart
Edmon Ryan
as Lieutenant Patrick O'Reilly
Wilfred Walter
as Blind Jake
Arthur E. Owen
as Dumb Lou
Alexander Field
as Fred Grogan
Gerald Pring
as Henry Stuart
O.B. Clarence
as Prof. John Dearborn (voice)
May Hallatt
as Police Constable Griggs
Bryan Herbert
as Police Sgt. Walsh
Charles Penrose
as Morrison, undercover detective
Julie Suedo
as Orloff's Secretary
Edgar Wallace
Novel
Walter Summers
Director
Patrick Kirwan
Screenplay
John Argyle
Producer
Guy Jones
Original Music Composer
Bryan Langley
Director of Photography
Jan Van Lusil
Additional Dialogue
Hamilton G. Inglis
Production Manager
Harry Benson
Sound Supervisor
A.E. Rudolph
Sound Recordist
Ted Richards
Editor
Duncan Sutherland
Art Direction
Jack Martin
Assistant Director
Ronald Anscombe
Camera Operator