In the final summer of the 20th Century, humanity faces a shocking revelation of not being Earth's sole rulers as colossal creatures known as 'Kaiju' emerge, with Godzilla reigning supreme as the ultimate monster. After a prolonged battle against the Kaiju spanning fifty years, humans, facing repeated defeats, make plans to flee Earth. By 2048, a select few chosen by an A.I.-controlled central government board the spaceship 'Aratrum' bound for 'Tau Cetus e', a planet over 11.9 light-years away. However, upon arrival after two decades, they discover Tau e's environment drastically differs from Earth's, rendering it inhospitable. Haruo, who witnessed his parents' demise by Godzilla at a young age, harbors a single-minded goal for 20 years: to defeat Godzilla and reclaim Earth. As the ship's conditions deteriorate and emigration seems impossible, Haruo leads the 'Earth Returnists' in a perilous journey back to Earth through hyperspace. Returning to Earth after 20,000 years, they find a world ruled by Godzilla. Will humans reclaim their home against this ancient threat, and what lies ahead for Haruo in this new reality?