The story revolves around a second‑year high school student, Daiti Manatsu, who notices in the evening, before the start of summer vacation, a strange round rainbow on television that was floating across the sky above Tanegashima Island. Earlier, Daiti had already seen this rainbow. Along with memories of his father"s mysterious death and a chance meeting between a girl and a young man, Daiti is on that island. At that time an alarm signal blares from a building marked "Earth Engine," which instantly disappears. Someone asks Daiti, if he is the captain, that he should know that recently robotic impostors from the planet Uranus, called KILL‑G‑GANG, have arrived on the island. A battle near sparkling stars is about to begin.
BONES Japan