The film is inspired by Bazhov's folk tale, The Mistress of the Copper Mountain, and tells a captivating story rooted in Russian legend and mythology. It begins with the story of Stepan, a skilled miner who encounters the mysterious and enchanting Mistress of the Copper Mountain, also known as Kseniya. She is a beautiful, green-eyed woman who watches over the copper mines and possesses incredible treasures.
Despite her divine and enigmatic presence, Stepan shows a lack of respect when he refers to her as "wench," an act she unexpectedly appreciates, recognizing his bravery. She reveals herself to him and issues a warning to the local bailiff, Severyan Nazarovich. In a commanding tone, she orders him to leave Krasnogorka, threatening him with her power: “The Mistress of the Copper Mountain orders you, ye stinking goat, to get out of Krasnogorka.” She promises Stepan that if he relays her message, she will marry him, establishing an extraordinary bond between the mortal and the divine.
However, her message enrages the bailiff, leading to Stepan being flogged, condemned to work in a mine, and only fed dog food. Miraculously, the Mistress visits him in his dire circumstances, frees him from the mine, and shows him a treasure trove of riches, including the image of a girl he has never met—his daughter. She reveals her true name as Kseniya and once again offers marriage, but Stepan, faithful and honest, admits that he has already promised to marry another woman, Nastya. The Mistress is momentarily upset but appreciates his loyalty and bravery, rewarding him with a malachite casket filled with jewelry for his bride, cautioning him never to think of her again.
After the death of the bailiff, Stepan is freed from his obligations to the Mistress, and he marries Nastya. Despite his new life, he continues to have visions of the Malachite Lady and often sees small lizards—her loyal servants. The Mistress continues to watch over Stepan’s family, especially his daughter, Tanyusha, who inherits her mother's curiosity about gemstones and lizards. Stepan's family grows as Nastya gives birth to a daughter, Tanyushka, and a son, Melesha. Stepan frequently visits the copper mine, sometimes accompanied by Tanyushka, and remains haunted by memories of the Mistress.
Tragically, during one of these visits, Stepan shoots himself in the chest but survives, though he stops speaking to the Mistress afterward. Years pass, and Stepan becomes older, with his daughter Tanyushka, a beautiful girl with a fondness for lizards, capturing the attention of many suitors. Among them is Vasily Turchaninov, a young nobleman and the son of a mine owner, who falls deeply in love with her. Stepan even dreams of seeing the famous malachite room at the imperial palace, and he asks his wife to wear the jewelry from the Malachite Casket, hoping to see its beauty.
However, Tanyushka, proud and independent, decides to test Vasily’s affection by demanding to see the malachite room herself. She claims the jewelry "warms her up" as if she is sitting by a fire, instead of wearing it for admiration. When Vasily visits the palace, the nobles mock his simple clothes, and Tanyushka sees their superficiality. Disappointed and disillusioned, she turns away from Vasily, leaning against the malachite wall, and eventually melts away, returning home to her mother and brother.
The story leaves a lingering sense of magic, loyalty, and tragic beauty, highlighting the deep connection between humans and the mystical forces guarding their fate. Throughout the narrative, themes of fidelity, pride, and the allure of dreams play a central role, along with the symbolic significance of the copper mountain and its treasures. The Mistress of the Copper Mountain remains an enduring tale of love, mystery, and the mystical power of the elements, echoing the enchanting traditions of Russian folklore.