The main character of this film, Konstantin Karetov (played by Dmitry Goncharov), is a boy from a working-class family who devotes all his time to self-defense, hoping to soon obtain the academic title of Master of Sports. Kostya lives with his mother and younger sister, without his father, in a provincial Russian town. Kostya's passion for sports runs counter to his mother's (Elena Iacovleva) ideas about what it should be like to be a real man. The mother believes that all this occupation with self-defense is just a hobby, and that more time should be devoted to study, work and supporting the family. She had bitter experience of similar choices when she herself, in her youth as a budding gymnast, had, through the misfortune of an accident, had to put a line under her sports career. But Kostya does not let his mother influence him, because among real athletes, there are only people who give themselves unconditionally to their goal. He is supported by his coach and Master Nikolai Svonarev (Vladimir Nestov), who in his eyes is a substitute father.
The real test for Kostya is the unrequited love for his classmate Lyube (Marina Bolonkina). The girl is not very interested in novice athletes, without money, without a profession and without sporting success yet. She likes distractions, expensive cars, the good life. A misfortune in Kostya's family aggravates an already complicated situation: his mother is taken to intensive care and has to undergo an expensive operation. Then the story develops at full speed, but we cannot get ahead of it: how Konstantin Karetov's life develops, you will find out for yourself in the near future.