Adaptation to the screen of the short story "Souchastniki" by A. Romov.
The young police lieutenant Kosyrev is assigned to the northern fishing kolkhoz. On the eve of his arrival, a large sum of money was stolen from the safe. Suspicion falls on the repeat offender Plague, who hides in a forest reserve and takes a forester and a groom as accomplices, whom he later kills. In pursuit of criminals (on a boat along the river and the lake), the young lieutenant wins his first victory ...