Aliens have been emigrating to Earth secretly, but only a handful knows about this truth. Living in such a society, the main character Hiroyuki Kudo begins working at a private security organization E.G.I.S. (Enterprise of Guard and Investigation Services). The organization takes care of cases related with aliens, and Hiroyuki works day and night to protect peace. However, there lies a huge secret in him, which he himself is not aware of. He carries Ultraman Taiga’s “particle of light”. The new story begins as Taiga’s powers revive from Hiroyuki’s body!