Inventor Goro Ibuki creates a humanoid robot named Jet Jaguar. It is soon seized by an undersea race of people called the Seatopians. Using Jet Jaguar as a guide, the Seatopians send Megalon as vengeance for the nuclear tests that have devastated their society.
Inventor Goro Ibuki
Hiroshi Jinkawa
Rokuro 'Roku-chan' Ibuki
Lead Seatopian Agent
Emperor Antonio of Seatopia
Gigan (as Kengo Nakayama)
Emperor Atonio of Seatopia (voice)
Godzilla (archive footage) (uncredited)
March 17, 1973
Inventor Goro Ibuki
Hiroshi Jinkawa
Rokuro 'Roku-chan' Ibuki
Lead Seatopian Agent
Emperor Antonio of Seatopia
Gigan (as Kengo Nakayama)
Emperor Atonio of Seatopia (voice)
Godzilla (archive footage) (uncredited)
