An underage house spirit named Kuzka finds his way into a typical Soviet flat and turns the life of a little girl Natasha into a fairy tale.

Prequel to Kuzya's story tells about his adventures in the woods, and how he got into Natasha's apartment.

Baba Yaga didn't tolerate Kuzya's escape, so she infiltrated Natasha's apartment to return him into the woods.

It is the last film in series "Little Brownie Kuzya".