Geologist Jiro Tate
Seajacker Samba
Seajacker Zamba (as Willy Dorcey)
Elliott Rhoades (English version only)
Doctor Hatsuyama
Seajacker Munk
Patricia Haber (English version only)
Seajacker Kifal
Chief Steward Terada
Chief Engineer Kusai (as Joe Shishido)
TV Director Fukami
Commander of Defense Katsuragi
Captain Munekata
Boatswain Nishizawa
Reporter Tatsuya Iwado
Reporter (uncredited)