Sidor Sidorovich and Fyokla Fyodorovna, a widow and widower who lived in Moscow next door, start a family, and their daughters Toma and Fira become half-sisters. As befits an evil stepmother, Fyokla begins to think about how she could exterminate her stepdaughter Toma. To begin with, she seeks advice from Baba Yaga, who lives in their city, but receives such terrible recommendations that she does not dare to use them, fearing to fall under a criminal article.