Nina receives news that her grandfather Pavel Alekseevich Nazarov was hospitalized with a massive heart attack. The girl urgently leaves for Staroselsk to find out what happened to her grandfather. When Nina arrives in the town, her former classmate, the boorish businessman Slavik, and her grandfather's successor as school director, the insecure Anton, begin to show attention to her. Moreover, operative Viktor finds fault with her every time over trifles.