John Archer
Jim Barnes
John Archer
Jim Barnes
Warner Anderson
Dr. Charles Cargraves
Tom Powers
General Thayer
Dick Wesson
Joe Sweeney
Erin O'Brien-Moore
Emily Cargraves
Steve Carruthers
Businessman at Meeting (uncredited)
Franklyn Farnum
Factory Worker (uncredited)
Jack Gargan
Businessman at Meeting (uncredited)
Everett Glass
Mr. La Porte (uncredited)
Kenner G. Kemp
Businessman at Meeting (uncredited)
Knox Manning
Himself (uncredited)
Mike Miller
Undetermined Secondary Role (uncredited)
Irving Pichel
Off Screen Narrator of Woody Woodpecker Cartoon (voice) (uncredited)
Cosmo Sardo
Businessman at Meeting (uncredited)
Grace Stafford
Woody Woodpecker (voice) (uncredited)
Bert Stevens
Businessman at Meeting (uncredited)
Ted Warde
Brown (uncredited)
Robert A. Heinlein
Screenplay
Alford Van Ronkel
Screenplay
Irving Pichel
Director
George Pal
Producer
James O'Hanlon
Screenplay
Duke Goldstone
Editor
Lionel Lindon
Director of Photography
George Sawley
Set Decoration
Leith Stevens
Original Music Composer
Lee Zavitz
Special Effects
Ernst Fegté
Production Design