Charlton Heston

Stewart Graff

Ava Gardner

Remy Royce-Graff

George Kennedy

Sgt. Lew Slade

Lorne Greene

Sam Royce

Geneviève Bujold

Denise Marshall

Richard Roundtree

Miles Quade

Marjoe Gortner

Jody

Barry Sullivan

Dr. Willis Stockle

Lloyd Nolan

Dr. James Vance

Victoria Principal

Rosa Amici

Walter Matthau

Drunk

Monica Lewis

Barbara

Gabriel Dell

Sal

Pedro Armendáriz Jr.

Chavez

Lloyd Gough

Bill Cameron

John Randolph

Los Angeles Mayor

Kip Niven

Walter Russell

Scott Hylands

Asst. Caretaker

Donald Moffat

Dr. Harvey Johnson

Jesse Vint

Buck

Alan Vint

Ralph

John Elerick

Carl Leeds

John S. Ragin

Chief Inspector

George Murdock

Colonel

John Dennis

Brawny Foreman

Gene Dynarski

Dam Caretaker

H.B. Haggerty

Pool Player

Tim Herbert

Las Vegas Man

Josh Albee

Boy with Radio (uncredited)

Joan Blair

Pawnbroker's Wife (TV version) (uncredited)

Reb Brown

Young Man on Motorcycle (uncredited)

Polly Burson

Earthquake Survivor (uncredited)

Ric Carrott

National Guardsman (uncredited)

David S. Cass Sr.

Sherriff Merle (uncredited)

Lonny Chapman

LAPD Captain (uncredited)

Sam Chew Jr.

Tony (Kathie's Husband) (uncredited)

Erik Cord

Office Worker (uncredited)

Kenny Endoso

Bar Cook (uncredited)

Jeannie Epper

Blonde Woman (uncredited)

Bruce M. Fischer

Man (uncredited)

Ernest Harada

Seismologist (uncredited)

Jerry Hardin

Man (uncredited)

Bob Harks

Man Fleeing Movie Theatre (uncredited)

Diana Herbert

Woman (uncredited)

Bert Kramer

Policeman (uncredited)

Paul LeClair

National Guardsman (uncredited)

Karl Lukas

Man (uncredited)

Jimmy Nickerson

Seismology Graduate Student (uncredited)

Stuart Nisbet

Man on Loudspeaker (voice) (uncredited)

Frances Osborne

Housewife (uncredited)

Charlie Picerni

Pool Player (uncredited)

Leoda Richards

Emergency Soup Kitchen Worker in Wilson Plaza (uncredited)

Debralee Scott

Kathie (TV version) (uncredited)

Dean Smith

Pool Player (uncredited)

Eddie Smith

Citizen (uncredited)

Arthur Tovey

Citizen (uncredited)

Keith Walker

Man on the Radio (voice) (uncredited)

Sandy Ward

Studio Guard (uncredited)

Dick Warlock

Diver at Hollywood Reservoir (uncredited)