At night, a terrible event occurs in the psycho-neurological department for adolescents - one of the patients almost dies. Adults assume that the culprit of the night incident is one of the guys. Doctors fear that history will repeat itself and end in tragedy. There is a version that teenagers play "dog buzz", a game of suffocation at night. Ivan Khristoforov, a talented psychiatrist who treats his young patients not so much with pills as with pedagogical methods, must figure everything out and stop the deadly game. But it turns out that finding the culprit is the easiest thing. It is much more difficult to save his soul - this becomes the main goal of Khristoforov. For this he is ready to sacrifice everything.