After a fishing boat is attacked, the sole surviving crew member realizes it is none other than a resurrected Godzilla. However, efforts to bring the story to light are suppressed by the Japanese government amid growing political tensions between the United States and the Soviet Union, who are both willing to bomb Japan to stop the monster.
A submarine expedition to salvage the remains of Mechagodzilla is thwarted by a massive dinosaur named Titanosaurus. An Interpol investigation leads biologist Ichinose to uncover the work of Dr. Mafune and his mysterious daughter Katsura. Aligned with the Black Hole Aliens, Katsura's life becomes entwined with the resurrected machine.
A mysterious extraterrestrial being resembling Godzilla rapidly approaches Earth. The monster, dubbed SpaceGodzilla, lands to challenge the King of the Monsters.
