A young guy Maxim introduces his parents to his favorite girl Nastya, they are in love and are going to get married. In addition, it turns out that Nastya is pregnant, and Maxim happily accepts this news. It would seem that nothing will overshadow the happiness of the future young family.... The father's intuition makes him turn to the past. Is it a coincidence that his son's girlfriend comes from the town of Snegov, where he had an affair with a woman many years ago? Worry for his son and a terrible hunch stir the father's heart. Mikhail goes to Snegov, where Vera, Nastya's mother, confirms the guess: the girl is his daughter, which means that the young people are brother and sister... Deep feelings, love, sense of duty and cruel fate fall on the heroes of the movie....