Jonathan Clark
Gene Barry
Eve Wingate
Valerie French
Admiral
Paul Birch
Radio Newscaster Ward Mason
Paul Frees
Su Tan
Marie Tsien
Gorki
Charles Bennett
Spokesman
John Bleifer
2nd Man
Irvin Ashkenazy
Dr. Schmidt
David Bond
Taxi Driver
Philip Van Zandt
Russian Marshal
Mel Welles
Interrogator
Peter Norman
Prof. Klaus Bechner
George Voskovec
Ivan Godofsky
Azemat Janti
The Soviet General
Stefan Schnabel
Dr. Karl Neuhaus
Friedrich von Ledebur
Mr Ingram
Ralph Clanton
The Alien
Arnold Moss
Soviet Prison Physician
Monty Ash
Soviet Col. Gregor
Theo Marcuse
Director
William Asher
Producer
Helen Ainsworth
Special Effects
Ray Harryhausen
Screenplay
John Mantley
Director of Photography
Henry Freulich
Art Direction
Ross Bellah
Editor
Jerome Thoms
Novel
Set Decoration
Frank Tuttle
Executive Producer
Lewis J. Rachmil
Second Unit
Will Sheldon
Sound Director
Ferrol Redd
Original Music Composer
Mischa Bakaleinikoff