K12, prison city. The sky above it is hidden behind an eternal veil of clouds, the borders are delineated by a high Wall, and the townspeople hide their faces under masks. There are no police here; gangster groups rule the streets. This city lives by its own laws. It was here that Maxim Serov, a teenage computer genius nicknamed Mockingbird, was exiled and deemed a danger to society. But the corrupt officials who sent Maxim to certain death had no idea that the young man himself was striving to get into K12 in order to take part in the Rat Race and win the most valuable prize - the right to leave the prison city. And that he needs the prize not only for himself.