On Klobouk Hill, which rises above the marshy forests, stands a bell tower, and there reigns Lady Fog, who rules the entire region unseen. No matter what the reformed bandit Jerka Berka claims, she is the true mistress here. And then there is the righteous Jan, who would never steal from anyone, not even the robber himself. And Jan has a lot of work to do. He must constantly rescue his brother Matouš, who has fallen in love with the robber's daughter Tereza, and he must also help the wild girl Anděla regain her true human form. Will Mrs. Mlha help him?