Full Credits
24 members

Richard Dix
John Sinclair / John Carter

Lynn Merrick
Joan Martin Sinclair

Rhys Williams
Ernie Sparrow

James Cardwell
Fred (Doc) Graham

Tom Kennedy
Ferdinand / Hammerlock

Sam Ash
Gibson Motor Car Co. Executive (uncredited)

Egon Brecher
Dr. Rose (replaced by Frank Reicher) (uncredited)

Charles Coleman
Sinclair's Butler (uncredited)
Otto Forrest
The Whistler (uncredited)

Byron Foulger
Georgie (uncredited)

Martín Garralaga
Tony, Fruit Peddler (uncredited)

John Hamilton
Doctor (uncredited)

Stuart Holmes
Sinclair Executive (uncredited)

Wilbur Mack
Sinclair Executive (uncredited)
Charles Marsh
Sinclair Executive (uncredited)

Harold Miller
Sinclair Executive (uncredited)

Forbes Murray
Sinclair Executive (uncredited)

Gigi Perreau
Bobbie (uncredited)

Frank Reicher
Dr. Rose (uncredited)

Clinton Rosemond
Train Porter (uncredited)

Frank J. Scannell
Druggist (uncredited)

Minerva Urecal
Georgie's Wife (uncredited)

Robert B. Williams
Pharmacist (uncredited)

Douglas Wood
Paul Kitridge - Attorney (uncredited)
10 members
William Castle
Director
Chris Beute
Assistant Director
William Castle
Writer
Wilfred H. Petitt
Writer
Allan Radar
Story
Rudolph C. Flothow
Producer
George Meehan
Director of Photography
Mario Castelnuovo-Tedesco
Original Music Composer
Jack A. Goodrich
Sound
Dwight Caldwell
Editor