Our contemporary Seryoga from St. Petersburg goes on another vacation to a small uninhabited island on Lake Vuoksa, to relax, as they say, from the bustle of the city, soul and body. But either the gods played a cruel joke with him, or the fate of the villain made a setup, in general, he landed right on the night of the Slavic holiday of Kupala. And the world so familiar to him immediately collapsed...