Koschei the Immortal, whose daughter has died, wants to find a replacement for her and organizes searches all over the world. It turned out that exactly the same girl named Masha lives in Leningrad. By cunning and deception she is kidnapped and taken to Koshchei. Masha's younger brother Mitya goes in search of his sister to Koshcheev's country. The brave boy, with the help of his new friends - Jackdaw with Galchonok, the Cheerful Chimney Sweep and the Master of Golden Hands, defeats the villain, rescues his sister from captivity and the dark kingdom of Koshcheevo becomes a land of goodness and justice.