Endless warfare and environmental pollution has brought forth giant monsters, which are a grave danger to the world. As a result, the Earth Defence Force (EDF) is created to protect the planet, uniting every nation. The organization is equipped with some of the best of technology and weapons, warships and soldiers, as well as mutants with super-human abilities. Godzilla, a giant mutant dinosaur, is claimed to be EDF’s only unstoppable opponent. The EDF’s best combat vehicle, the Gotengo, manages to corner Godzilla at the South Pole and bury him under the Antarctic ice, cryogenically freezing him.
Suddenly, monsters all appear around the world at major cities and the EDF promptly swings into action, attempting to drive away the monsters, but achieves little success. Then, after destroying much of their cities, the monsters vanish as an enormous alien mothership hovers over Tokyo. Aliens called the Xiliens then reveal themselves, insisting they are friendly and that they have eliminated the monsters. They also warn the Earth’s governments about impending danger in the form of a planet called Gorath that will crash into Earth. Consequently, the Space Nations is established, an alliance that would unite the universe. Ozaki, Miyuki, and several others distrust them. After much researching and undercover work, they discover the Xiliens are up to no good. Finally, the Xiliens turn out to be evil and unleash the monsters to destroy Earth. Gigan is also revived and joins in the frenzy. The EDF eventually loses and Earth’s cities are destroyed. wiki