Outer space, the far future. A lone seed ship, the Sidonia, plies the void, ten centuries since the obliteration of the solar system. The massive, nearly indestructible, yet barely sentient alien life forms ...

In this world, men live on islands floating in the clouds. But the heavens are also the domain of "dragon fish", gigantic monsters hostile to humans and their ships ... Yuu is one of the guards responsible f...