James Daly
/ Jim Briscoe / Major Gaylord / A cartoonist / Mr. White / Bill Tanner / Sergea...

Charlton Heston
/ Commander Schneider / Edward Rochester / Heathcliff / James Otis / Mitch Hend...

John Forsythe
/ Judd / Marv Payne / Capt. Sam MacKenzie / James Rexham / Maj. Peter Brook / P...

John Cannon
Self - Announcer (voice)

Everett Sloane
/ Mike Hudson / Walter Winkworth / Giovanni / Korolenko / Ben Royce / Aaron Bur...

Richard Kiley
/ Merrick / Richard Baker / Edward Dean / Fred Baxter / Julian Hurst / Ralph Jo...

Leslie Nielsen
/ Mac / Edmund / Tallman / Karl / Stan Janicek / Dr. Roger Waring / Dr. Claybor...

Betsy Palmer
/ Ann Meade / Edith Olmstead / Dony Waller / Ellen Morrison / Mimi / Maureen Dr...

Berry Kroeger
Mr. Lawrence / Baron Tito Belcredi / Mr. Walkes / Sir Sagramor / / Rembrandt Va...

Shepperd Strudwick
/ Mac Taylor / Senator Greet / Nordlund / Hal Manning / Cassius

Vaughn Taylor
Billy / Mr. Racknall / Prof. Henry Lempkin / / Carlton Delafield / Admiral Luet...

Harry Townes
/ Eliot Nelson / Mr. Hager / Mr.Rogers / Karl Weber / Peter Hartley / Outarist

Nina Foch
Melissa Turner / Fran / Joyce / Lee Fouche / Barbara / / Belinda Cattson / Carr...

E.G. Marshall
/ Aaron Kinney / Harry Mork / Everett Metcalf / Dr. Shratt / George Banks

Bramwell Fletcher
/ Mr. Wynteringham / Governor Bell / Dr. Alderton

Hildy Parks
Fran / Mabel Prentice / Judy McDermott / Maggie Troy / Avery Dow / Doris Anderso...

Charles Korvin
/ Paul Collins / Philip Hausman / El Cameron / Francis / Julian Wilder / Gastma...

Skip Homeier
Theodore Jr. / The Boy / / Dickie Rogers / Peter Shea / Capt. Gene Lipton / Car...

James Gregory
Private Alan Pomeroy / George Monzo / Corey / Mr. Bales / Mr. Black / James Metc...

Edward Andrews
Fistar Marrock / Henry Horne / / Forest / C. Elliot Friday / Parker / Nils