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