Boris, a young merchant, confesses to his friend Kudrjáš that he is in love with Kátya Kabanová, who is married to Tichon. Tichon’s mother, Kabanicha, orders Tichon to make a trip to another city, complaining that he now spends more time with his wife than with her. Kátya confesses to her girlfriend Varvara her feeling that something disastrous is about to occur; she has a recurring dream in which she runs off with a lover. She begs Tichon not to leave, worried about what she might do in his absence. As Tichon is about to depart, Kabanicha makes him order Kátya to be faithful while he is gone.

Varvara encourages Kátya’s interest in Boris, stealing the key for the now-locked garden gate and giving it to Kátya for a future rendezvous with Boris. Later on, Kudrjáš comes to the garden and serenades Varvara. Boris arrives and Kudrjáš warns him of the dangers he faces in courting a married woman. Kudrjáš and Varvara leave, and Kátya soon appears. At first she rejects Boris, but she eventually admits her love for him. They go for a walk in the moonlight and declare their mutual love.

Ten days later, Tichon returns unexpectedly and Kátya is overwhelmed by guilt. She interprets an approaching thunderstorm as a divine signal of her sin and publicly confesses the affair to Tichon, Kabanicha, and the villagers. Kátya rushes out into the oncoming storm. At the banks of the Volga, the villagers search for Katya, while Kudrjáš and Varvara decide to elope. Kátya enters, longing for death but also wanting to see Boris again. He arrives, embraces her and tells her that he is being sent to a trading post in Siberia. After their farewell, Katya throws herself into the Volga and drowns. The search party returns and retrieves her body from the river. Tichon accuses Kabanicha of causing Kátya’s death, but she ignores him, impassively thanking the villagers for helping with the search.