"An edited version of the 4½ hour serial about a mad scientist who attempts to rule the world by creating various elaborate inventions."
Bela Lugosi
as Dr. Alex Zorka
Dorothy Arnold
as Jean Drew
Robert Kent
as Capt. Bob West
Edwin Stanley
as Dr. Fred Mallory
Regis Toomey
as Lt. Jim Daley
Jack C. Smith
as Monk
Edward Van Sloan
as Jarvis
Dora Clement
as Ann Zorka
Anthony Averill
as Rankin
Hugh Huntley
as Perkins
Monte Vandergrift
as Jarvis Goon
Frank Mayo
as West's Boss
Jim Farley
as Harbormaster
Eddie Acuff
as Mac
Ed Wolff
as The Robot
Roy Barcroft
as Parker (uncredited)
Lee J. Cobb
as Road Crew Foreman (uncredited)
Charles King
as Car-Crash Cop (uncredited)
Ford Beebe
Director
Saul A. Goodkind
Henry MacRae
Associate Producer
George H. Plympton
Screenplay
Basil Dickey
Mildred Barish
Ralph M. DeLacy
Art Direction
Jerome Ash
Director of Photography
William A. Sickner
Alvin Todd
Editor
Irving Birnbaum
Wyllis Cooper
Original Story
Joseph Gluck