Flying through the emptiness of space is Barcelona 17, the starry home of hundreds of millions of people, the ship is a generation. He flies, abandoned by the inhabitants. Simon Paul is a raven, a sky-looter, a descendant of those who once doomed all the inhabitants of the city to death in the void. Descendant of executioners? No! the descendant of the biggest losers in habitable space. He feasts on forgotten things, fights domestic robotics and is generally happy, as any boy of fifteen who has real wings can be happy. But one day he meets the Devil. Artificial intelligence that originated on a forgotten computing module. And Simon has to learn the bitter truth: Machines go crazy too.