New Year's detective story with thriller elements for children: young and old. On New Year's Eve, Petya's mother decided to give him a gift and convince him of the existence of Santa Claus. However, she made one mistake. As a result, their apartment was robbed on New Year's Eve. Second-grader Petya Ivushkin, trying to find out the reality of the existence of Santa Claus, accidentally finds out the circumstances of the theft. He tries to track down the thief, but he himself falls into the clutches of ferocious and disgusting villains. Thanks to his resourcefulness, courage and knowledge received from his parents, he manages to free himself. How prepared are our children for the sometimes harsh and cruel world? What can they oppose to evil, will they be able to cope with the superior forces of the enemy, fight and win, or will they only cry and complain about difficulties? Can parents prepare a little person for the difficulties and dangers of real life? And where do those terrible adults come from, whom both small and large should be afraid of? Optimism and faith in the good and the good run through the story as a red thread to the reader.