Four months ago, the aliens began to invade the earth, and the earth set up a "Alien Countermeasures Headquarters". In fact, there are only two people in this department, Arikawa (voiced by Toyonaga Toshiyuki) and Xiaobai (voiced by Hirakawa Daisuke). The aliens who appeared took only one action, that is, one person came to provoke the boy every day. The only one who can fight with the aliens is a boy who lost his memory and was picked up by Arikawa-"Scarecrow" (voiced by Kimura Ryohei). Under the care of Arikawa and Xiaobai, he fights with the aliens every day. On the other hand, Scarecrow is also very concerned about his previous memories. Who was he before he met Arikawa, and where were his parents and friends? At the same time, he also had various questions: Why do aliens only fight with themselves? If I lose, will the earth be destroyed? If I sacrifice myself, can the earth be protected? Will there be answers in the mobile phone left behind?