After leaving the hospital, Sergeant Katsuba, who has bid farewell to frontline service, travels to a provincial town to teach military science to cadets. However, his relationship with the 17-year-old boys does not go well: they consider their instructor to be unfair and overly critical...

This is a last of 3 movies about 3 friends (the other two are "Kortik" and "Bronzovaya Ptitsa"). The gang has grown up and in this movie they discover and help to stop criminal activity on the factory and in their neighborhood.