On New Year's Eve, Pavel mistakenly takes someone else's coat, in which he finds expensive jewelry. At home, he realizes that his daughter's letter to Santa Claus remains in the pocket of his lost coat. The father of the family, together with his wife, is trying to find out what exactly the girl wished for. But six-year-old Varya is afraid to talk about her dream, otherwise it won't come true. In order to preserve the child's faith in miracles, parents will have to find a letter that was lost in the vast city of Moscow, and at the same time return the found gift.