Glenn Ford

President Richardson

Robert Vaughn

Senator Barkley

Masao Kusakari

Doctor Shûzô Yoshizumi

Yumi Takigawa

Asami Noriko

Henry Silva

General Garland

Bo Svenson

Major Carter

Stephanie Faulkner

Sarah Baker

Stuart Gillard

Doctor Ed Meyer

Cec Linder

Doctor Latour

Chuck Connors

Captain McCloud - HMS Nereid

George Kennedy

Admiral Conway

Olivia Hussey

Marit

Edward James Olmos

Captain Lopez

Isao Natsuyagi

Commander Nakanishi

Julie Khaner

Secretary - Palmer Station

George Touliatos

Col. Rankin

Sonny Chiba

Dr. Yamauchi

Tsunehiko Watase

Yasuo Tatsuno

Kensaku Morita

Ryûji Sanazawa

Toshiyuki Nagashima

Akimasa Matsuo

Nicholas Campbell

Radio Operator - Palmer Station

Chris Wiggins

Dr. Borodinov

Eve Crawford

Dr. Irma Ollich

John Bayliss

Major King

John Rutter

Sailor #1 - HMS Nereid

Alf Humphreys

Sailor #2 - HMS Nereid

Michael Tough

Young Sailor - HMS Nereid

Ken Ogata

Prof. Tsuchiya

William Binney

White House Aide Simmons

Stuart Gillard

Dr. Ed Meyer

Colin Fox

Spy Z

Ken Pogue

Dr. Krause

Alberta Watson

Litha (uncredited)

Mitsuko Oka

Tatsuno Yoshiko

Takashi Noguchi

Doctor's Assistant

Nenji Kobayashi

Doctor's Assistant #2

Haruki Kadokawa

Crew Member

Chū Takatsuki

Crew Member