Have you ever been chosen by the forces of light? No? Katya has never had the chance to do this either. But anything can happen when you go from a typical high-rise building to an old house where your grandmother lives. It is within its ancient walls that she accidentally learns disturbing news that forces the girl to go into the distant past. On a journey full of dangers, where the machinations of assorted evil spirits await her at every step. Because the forces of darkness decided to stop time: to block the source from which it flows, like a river. Then, in the chaos that reigns, they will be able to enslave the world of people. Will an ordinary schoolgirl have enough strength and courage to prevent trouble?