AD. 2058, on Clayad, the 3rd planet of the Ypserlon system, 43 light years from Earth; aliens suddenly raid the planet. The residents of Clayad must escape the planet. In the confusion of the escape, the children are separated from their parents and board the training spaceship Janous. After many sacrifices, they manage to arrive at the 4th planet, Belwick. However, Belwick is already at war, so the 13 children continue towards Earth on their own.

(Source: AnimeNfo, edited)