It is the year 2312: Humanity has populated parts of the solar system, established habitats on asteroids, and built a moving city on Mercury. In all these new worlds, it has experimented with new forms of society that are in conflict with one another. Now, human civilization faces its greatest challenge - for as far as humanity has developed, its fall can be just as deep. A murder occurs on Mercury, and a young woman, who has been a creator of cities, finds herself increasingly entangled in a conspiracy that aims for one thing: destruction.