Walter Pidgeon

Admiral Harriman Nelson

Robert Sterling

Captain Lee Crane

Barbara Eden

Lieutenant Cathy Conners

Peter Lorre

Comm. Lucius Emery

Joan Fontaine

Dr. Susan Hiller

Michael Ansara

Dr. Miguel Alvares

Frankie Avalon

Lieutenant Chip Romano

Regis Toomey

Dr. Jamieson

John Litel

Vice Admiral B.J. Crawford

Howard McNear

Congressman Llewellyn Parker

Henry Daniell

Dr. Zucco

Robert Easton

Sparks

Charles Tannen

CPO Mack Gleason

Mark Slade

Seaman Jimmy 'Red' Smith

Del Monroe

Seaman Kowski

Jonathan Gilmore

Seaman George Young

Anthony Monaco

Cookie

Skip Ward

Crew Member

Michael Ford

Crew Member

William Herrin

Crew Member (Uncredited)

Robert Buckingham

Crew Member (Uncredited)

Richard Adams

Crew Member (Uncredited)

Jimmy Murphy

Crew Member (Uncredited)

George Diestel

Lieutenant Hodges (Uncredited)

Larry Gray

Dr. Newmar (Uncredited)

David McLean

Ned Thompson (Uncredited)

Edward Rickard

Officer (Uncredited)

Charles Dierkop

Seaview Pilot (Uncredited)

Kendrick Huxham

UN Committee Chairman (Uncredited)

Art Baker

UN Commentator (Uncredited)

Rodger Terry

Guard (Uncredited)

Brad Brown

Guard (Uncredited)

Raoul Freeman

Delegate (Uncredited)

Al Bain

Delegate (Uncredited)

Harry Baum

Delegate (Uncredited)

Benjie Bancroft

Delegate (Uncredited)

Michael Cirillo

Delegate (Uncredited)

Harry Denny

Delegate (Uncredited)

John Giovanni

Delegate (Uncredited)

Bhupesh Guha

Delegate (Uncredited)

Esther Ying Lee

Delegate (Uncredited)

Robert Locke Lorraine

Delegate (Uncredited)

George Nardelli

Delegate (Uncredited)

Paul Power

Delegate (Uncredited)

Paul Ravel

Delegate (Uncredited)

Scott Seaton

Delegate (Uncredited)

Leslie Sketchley

Delegate (Uncredited)

Ray Spiker

Delegate (Uncredited)

Hal Taggart

Delegate (Uncredited)

Robert Strong

Delegate (Uncredited)

Ron Nyman

Crew Member (uncredited)