Lady Macbeth of the Mtsensk District
One example is the main theme of Katerina's aria, "Seryozha, khoroshiy moy", from the fourth act of "Lady Macbeth of the Mtsensk District". It accompanies Katerina as she reunites with her lover Sergei. The aria's beauty comes as a breath of fresh air in the intense, overbearing tone of the scene. This goes well with the dialogue, as Katerina visits her lover in prison. The theme is made tragic when Sergei betrays her and finds a new lover upon blaming Katerina for his incarceration.