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