Gene Barry
Role: Clayton Forrester
Ann Robinson
Role: Sylvia Van Buren
Lewis Martin
Role: Matthew Collins
Les Tremayne
Role: General Mann
Frank Kreig
Role: Fiddler Hawkins (uncredited)
Vernon Rich
Role: Ralph Heffner
Sandro Giglio
Role: Dr. Bilderbeck
Ann Codee
Role: Dr. Duprey (uncredited)
Robert Cornthwaite
Role: Dr. Pryor
Cedric Hardwicke
Role: Commentary (voice)
Houseley Stevenson Jr.
Role: General Mann's Aide
William Phipps
Role: Wash Perry
Jack Kruschen
Role: Salvatore
Paul Birch
Role: Alonzo Hogue (uncredited)
Paul Frees
Role: Second Radio Reporter / Opening Announcer
Henry Brandon
Role: Cop at Crash Site
Peter Adams
Role: Pine Summit Fire Watcher (uncredited)
Eric Alden
Role: Man (uncredited)
Hugh Allen
Role: Brigadier General (uncredited)
Ruth Barnell
Role: Mother (uncredited)
Edgar Barrier
Role: Prof. McPherson (uncredited)
Russ Bender
Role: Dr. Carmichael (uncredited)
Oscar Blank
Role: Man in Church (uncredited)
Hazel Boyne
Role: Screaming Woman (uncredited)
Chet Brandenburg
Role: Man in Church (uncredited)
George Bruggeman
Role: Soldier (uncredited)
Nora Bush
Role: Woman in Church (uncredited)
Tony Butala
Role: Boy in Final Church (uncredited)
Mushy Callahan
Role: Burning Soldier at Pit (uncredited)
Dick Cherney
Role: Looter (uncredited)
Edward Colmans
Role: Spanish Priest (uncredited)
James Conaty
Role: Man at Pacific Institute of Science and Technology (uncredited)
Russ Conway
Role: Rev. Bethany (uncredited)
Martin Coulter
Role: Marine Sergeant (uncredited)
Vittorio Cramer
Role: First Radio Reporter (uncredited)
Pierre Cressoy
Role: Frenchman (uncredited)
Oliver Cross
Role: Scientist (uncredited)
Jane Crowley
Role: Woman in Church (uncredited)
Jim Davies
Role: Marine Commanding Officer (uncredited)
Helen Dickson
Role: Woman in Church (uncredited)
Ralph Dumke
Role: Buck Monahan (uncredited)
Jimmie Dundee
Role: Civil Defense Official (uncredited)
Al Ferguson
Role: Police Chief (uncredited)
Dick Fortune
Role: Marine Captain (uncredited)
Alex Frazer
Role: Dr. James (uncredited)
Frank Freeman Jr.
Role: Bum #2 Listening to Radio (uncredited)
Slim Gaut
Role: Radio Listener (uncredited)
Charles Gemora
Role: Martian (uncredited)
Ned Glass
Role: Well-Dressed Looter (uncredited)
Jack Gordon
Role: Man in Church (uncredited)
Fred Graham
Role: Looter (uncredited)
Joe Gray
Role: Looter (uncredited)
Herman Hack
Role: Worker Listening to Radio (uncredited)
Nancy Hale
Role: Young Wife (uncredited)
Virginia Hall
Role: Girl (uncredited)
Ted Hecht
Role: KGEB Reporter (uncredited)
Douglas Henderson
Role: Staff Sergeant (uncredited)
Gertrude Hoffmann
Role: Elderly News Vendor (uncredited)
Tex Holden
Role: Man in Church (uncredited)
Jimmie Horan
Role: Party Guest (uncredited)
Patricia Iannone
Role: Girl (uncredited)
Jerry James
Role: Reporter (uncredited)
Michael Jeffers
Role: Worker Listening to Radio (uncredited)
Dick Johnstone
Role: Man in Church (uncredited)
Carolyn Jones
Role: Blonde Party Guest (uncredited)
Don Kohler
Role: Colonel (uncredited)
Ivan Lebedeff
Role: Dr. Gratzman (uncredited)
Freeman Lusk
Role: Secretary of Defense (uncredited)
Herbert Lytton
Role: Chief of Staff (uncredited)
Wilbur Mack
Role: Official (uncredited)
George Magrill
Role: Traffic Cop (uncredited)
Mike Mahoney
Role: Townsman (uncredited)
John Mansfield
Role: Man (uncredited)
Joel Marston
Role: Military Policeman in Jeep (uncredited)
Sydney Mason
Role: Fire Chief, Crew #3 (uncredited)
John Maxwell
Role: Doctor (uncredited)
Mathew McCue
Role: Man in Church (uncredited)
David McMahon
Role: Minister, First Church (uncredited)
William Meader
Role: P.E. Official (uncredited)
Lee Miller
Role: Reporter (uncredited)
Ralph Montgomery
Role: Los Angeles Red Cross Official (uncredited)
Alvy Moore
Role: Zippy (uncredited)
Bob Morgan
Role: Injured Civil Defense Worker (uncredited)
Charles Morton
Role: Worker Listening to Radio (uncredited)
George Nardelli
Role: Military Officer (uncredited)
Stanley Orr
Role: Marine Major (uncredited)
George Pal
Role: Bum #1 Listening to Radio (uncredited)
Walter Richards
Role: Reporter (uncredited)
Robert Rockwell
Role: Forest Ranger at Crash Site (uncredited)
Walter Sande
Role: Sheriff Bogany (uncredited)
James Seay
Role: Air Force Bomber Pilot (uncredited)
Allen D. Sewall
Role: Man in Church (uncredited)
Lucile Sewall
Role: Woman in Church (uncredited)
Cora Shannon
Role: Old Woman (uncredited)
David Sharpe
Role: Looter (uncredited)
Teru Shimada
Role: Japanese Diplomat (uncredited)
Reginald Lal Singh
Role: Military Officer (uncredited)
Bobby Somers
Role: Deputy at Crash Site (uncredited)
Bert Stevens
Role: Man in Church (uncredited)
Charles Stewart
Role: Marine Captain (uncredited)
Jack Stoney
Role: Looter (uncredited)
Gus Taillon
Role: Elderly Man (uncredited)
Morton C. Thompson
Role: Reporter (uncredited)
Arthur Tovey
Role: Party Guest (uncredited)
Dale Van Sickel
Role: Looter (uncredited)
Dorothy Vernon
Role: Elderly Woman at Square Dance (uncredited)
Anthony Warde
Role: Military Police Driver (uncredited)
Bob Whitney
Role: Military Officer (uncredited)
Chalky Williams
Role: Worker Listening to Radio (uncredited)
Waldon Williams
Role: Boy (uncredited)
Bud Wolfe
Role: Rescuing Civil Defense Worker (uncredited)
Fred Zendar
Role: Marine Lieutenant (uncredited)