The heroine of the story - Natasha Krotova gets acquainted with the student Nikolai Sorokin - the adherent of the worldwide organization of the sleep "Allihora," where people are taught to manage both their own and other people's dreams. Natasha likes the unusual infatuation of a friend, and she joins him, becoming a hamilos - a pupil. But in the country of night dreams, everything is not as cloudless as it seems at first, and once Natasha, along with her mentor Lior, falls into a situation where both have to fight for their lives.