Yuuta volunteers to forget the person he loved most, and the movie spends two hours watching him try to remember why that was the right choice. The film refuses to let sacrifice be clean or noble. Instead it's messy, lonely, and the only honest thing any of these characters can do. By the end, you understand that some heroism isn't about saving the world, it's about choosing to lose yourself for someone else's future.

A year after the events of SSSS.GRIDMAN, the world is at peace, and almost no one remembers the kaiju, Gridman, or Akane Shinjou. Only Rikka and Utsumi still hold those memories. Yuuta, who once served as Gridman's host, has lost all recollection of the most important moments of his life. When a new kaiju appears, he seizes the chance to prove to himself that he can be the hero too, merging with Gridman once again. The film is a theatrical follow-up to both SSSS.GRIDMAN and SSSS.DYNAZENON, mixing mecha action and sci-fi with romance.