At the beginning of the 21st century, humans left most of the people on Earth, which was ravaged by Godzilla, and only selected people boarded the interstellar immigration ship Aratrum to the "Promised Land, Planet Tau-e" where they could migrate. However, this plan failed, and humans had to return to Earth again. However, the distortion of time and space caused by long-distance subspace travel caused the place where humans returned to become "Earth 20,000 years later." On this Earth, the protagonist Haruo and others, while being attacked by Godzilla, jointly implemented the "anti-Godzilla tactics" planned for 20 years with the aliens of the two races of Exif and Bilshald, and successfully defeated Godzilla through a desperate battle. However, the joy did not last long, and the real Godzilla "Godzilla Earth" hidden deep underground appeared. In the face of the overwhelming destructive power of the super-giant Godzilla that has evolved into this form, which has continued to grow and survive for 20,000 years, is 300 meters tall and weighs more than 100,000 tons, Haruo and others were defeated. The one who saved Haruo was Miana, a member of the "Futua" people who were regarded as the remnants of mankind. The Futua are the first humanoid life form they encountered on this Earth. Could they be the descendants of humans? "The god of Futua was also defeated by Godzilla, and now only eggs remain. Challengers and resisters were all swallowed up by flames and disappeared." Facing them like this, Haruo responded, "This is the last chance for humans to take back the Earth with their own hands." On the other hand, the commander of Birshald, Garg, was delighted to notice that the arrows used by Futua were made of "autonomous thinking metal body nanometal." This is made of the same material as the "Mechagodzilla" they developed at the foot of Mount Fuji in the 21st century as a "decisive weapon against Godzilla" and was destroyed before it was activated. This is proof that the development equipment at that time still exists today.