Godzilla vs. Megalon

Seatopia, an undersea civilization, has been heavily affected by nuclear testing conducted by the surface nations of the world. Upset by these tests, the Seatopians plan to unleash their civilization's beetle-like cyborg god, Megalon, to destroy the surface world out of vengeance. Jet Jaguar is used to guide Megalon to attack Tokyo with the Japan Self Defense Forces failing to defeat the monster. Goro Ibuki, his nephew Rokuro, and Goro's friend Hiroshi Jinkawa are off on an outing near a lake.