82 minutes
3/17/1973
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.
Katsuhiko Sasaki
as Inventor Goro Ibuki
Yutaka Hayashi
as Hiroshi Jinkawa
Hiroyuki Kawase
as Rokuro 'Roku-chan' Ibuki
Kanta Mori
as Japan Special Defense Forces Chief
Kotaro Tomita
as Lead Seatopian Agent
Ulf Otsuki
as Seatopian Agent
Sakyo Mikami
as Truck Driver's Assistant
Fumiyo Ikeda
as Man from Unit 1
Robert Dunham
as Emperor Antonio of Seatopia
Gentaro Nakajima
as Truck Driver
Ralph Jesser
as Antonio's Aide (Radio Operator in White)
Shinji Takagi
as Godzilla
Hideto Odachi
as Megalon
Tsugutoshi Komada
as Jet Jaguar
Masachika Mori
as Jet Jaguar
Kenpachirō Satsuma
as Gigan (as Kengo Nakayama)
Gorō Naya
as Emperor Atonio of Seatopia (voice)
Eisuke Nakanishi
as Narrator
Haruo Nakajima
as Godzilla (archive footage) (uncredited)