At the age of seventeen, Kostya became the European champion in sambo. He is a young and promising athlete, popular among girls and respected by his colleagues. In addition to sports, he studies, works and takes care of his sister, who has been unable to walk since birth. An accident ruined the life of the young champion, leaving him crippled. But fate gave him a second chance - a mysterious Voice offered a deal. A second life in return for a favor. Kostya accepted the deal on the condition that his sister would follow him. And the Voice gave its consent. Only now only one of them will acquire a body. The former champion will have to survive in a new, incredibly cruel world, where the strong rule and the weak die.