Michael Caine
Role: Brad Crane
Katharine Ross
Role: Capt. Helena Anderson
Richard Widmark
Role: Gen. Thaddeus Slater
Richard Chamberlain
Role: Dr. Hubbard
Olivia de Havilland
Role: Maureen Schuester
Lee Grant
Role: Anne MacGregor
José Ferrer
Role: Dr. Andrews
Slim Pickens
Role: Jud Hawkins
Bradford Dillman
Role: Maj. Baker
Fred MacMurray
Role: Maj. Clarance Tuttle
Henry Fonda
Role: Dr. Walter Krim
Cameron Mitchell
Role: Gen. Thompson
Christian Juttner
Role: Paul Durant
Morgan Paull
Role: Dr. Newman
Alejandro Rey
Role: Dr. Martinez
Don 'Red' Barry
Role: Pete Harris
Elizabeth Rogers
Role: Woman Scientist
Doria Cook-Nelson
Role: Mrs. Durant
Robert Varney
Role: Mr. Durant
Ernie F. Orsatti
Role: Duty Officer
Patrick Culliton
Role: Sheriff Morrison
John Furlong
Role: Cameraman
Barbara Costello
Role: Receptionist / Nurse
Jenifer Taurins
Role: Nurse
David Himes
Role: Radioman
Joey Eisnach
Role: Bee Boy
Stephen Powers
Role: Radarman
Chris Capen
Role: Lieutenant
Tony Haig
Role: Officer #2
Bill Snider
Role: Radarman #2
George Simmons
Role: Nurse
Arell Blanton
Role: Sergeant
Trent Dolan
Role: Radio Sergeant
John Williams
Role: Launching Officer
Steven Marlo
Role: Pilot #1
Phil Montgomery
Role: Mechanic
Marcia Nicholson
Role: Captain
Arthur Space
Role: Engineer
Chuck Hayward
Role: Standby Engineer
Glenn Charles Lewis
Role: Chemical Warfare Guard
Art Balinger
Role: Radio Announcer
Michael Sheehan
Role: Airman #1
Howard Culver
Role: Airman #2
Buzz Barbee
Role: Briefing Guest (uncredited)
Ken Clayton
Role: Dr. Moore (uncredited)
Marneen Fields
Role: Train Passenger (uncredited)
Bob Harks
Role: Townsman (uncredited)
Mike Johnson
Role: Burning Man (uncredited)
Jack Krupnick
Role: Train Passenger (uncredited)
Lawrence Moran
Role: Colonel's Son (uncredited)
Monty O'Grady
Role: Briefing Guest (uncredited)
John Otrin
Role: Wild Lines (uncredited)
Leoda Richards
Role: Briefing Guest (uncredited)
Norman Stevans
Role: Briefing Guest (uncredited)
