The watch repairman practices what is known as "parental rights" – he mercilessly beats his son Boris for every misdemeanor. The boy grows up intimidated, angry, trusting no one, and befriending no one. One day, while the students at the polytechnic school where Boris studies are busy with a physical education class, he deliberately destroys a model that the students have worked so hard to build. The teacher prevents a cruel punishment of the culprit. The school community takes on the responsibility of re-educating Boris. Considered lost.