Stuart Whitman
Adm. Michael Matthews
Acting
Robert Wagner
Brett
Acting
Rosemary Forsyth
Lia Holmes
Acting
Robert Colbert
Cmdr. Woody Patterson
Acting
Burr DeBenning
Aguila
Acting
Susana Miranda
Elena
Acting
Paul Stewart
Barton
Acting
Whit Bissell
Prof. Holmes
Acting
Richard Basehart
The President
Acting
Joseph Cotten
Dr. Ziegler
Acting
James Darren
Dr. Talty
Acting
Sugar Ray Robinson
Capt. Hunter
Acting
Charles Dierkop
Quinn
Acting
Larry Pennell
Bill Holmes
Acting
William Bryant
Capt. Lunderson
Acting
Robert Dowdell
Young Officer
Acting
Edward G. Robinson Jr.
Dr. Burkson
Acting
Sheila Allen
Blonde Woman
Acting
Tom Drake
Gen. Putnam
Acting
Johnny Lee
Tony
Acting
Glenna Sergent
Sally
Acting
Ray Didsbury
Security Guard
Acting
Erik L. Nelson
Triton Controller
Art
Paul Bradley
Scientist (uncredited)
Acting
Brent Dunsford
Technician (uncredited)
Acting
George Holmes
Scientist (uncredited)
Acting
Victor Toyota
Scientist (uncredited)
Acting