Synopsis
In 2019, as a new era is about to begin, a dimensional rift opens in the sky, revealing an alternate world called Shinkoku Nippon, where the sky and ground are swapped. This parallel world, steeped in traditional militaristic culture and frozen in a perpetual Showa period, invades our Japan using giant humanoid mecha named Garann and gas weapons called Genmu, which disable modern military equipment. With these advantages, Shinkoku Nippon quickly seizes control of the government, effectively conquering the nation and marking the start of the Reiwa era.
