Godzilla vs. Gigan

Astronauts Glenn and Fuji investigate Planet X and encounter mysterious aliens known as the Xiliens, who ask Earth's people to help save their world from "Monster Zero". In exchange for borrowing Godzilla and Rodan, the Xiliens offer a cure for cancer. As Glenn investigates, he develops a romance with Miss Namikawa and uncovers the Xilien's true intentions.

Godzilla has become a distant memory for Japan when the destruction of a US submarine raises alarms for Admiral Tachibana. His estranged daughter Yuri investigates the legend of the guardian monsters, who must rise to protect Japan against the vengeful spirits within Godzilla that seek to destroy both the nation and its people for the suffering they inflicted in the Pacific conflict.

An Okinawan prophecy that foretells the destruction of the Earth is seeming fulfilled when Godzilla emerges to return to his destructive roots. But not all is what it seems after Godzilla breaks his ally Anguirus's jaw. Matters are further complicated when a second Godzilla emerges, revealing the doppelgänger as a mechanical weapon.

With no means for defeating Godzilla Earth, mankind watches as King Ghidorah, clad in a golden light, descends on the planet. The heavens and earth shake once again as the war moves to a higher dimension.

At the turn of the century, all of the Earth's monsters have been rounded up and kept safely on Monsterland. Chaos erupts when a race of she-aliens known as the Kilaaks unleash the monsters across the world.