Ninth grade students from one of the Moscow schools are undergoing summer internship at a large carpool. Having quickly become familiar with the organization of the uncomplicated work of a repairman, the guys choose a supplier from their friendly team - and everyone finds practice in something useful. Only Seryozha Krasheninnikov (Krosh), with his humanitarian abilities and complete lack of interest in technology, clearly stands out from the friendly team. But an emergency occurs: a brand-new shock absorber disappears from the warehouse, and then the car. And the observant Krosh takes on the functions of a detective.
