How did Expressionism appear in the operas Wozzeck and Lulu by Alban Berg?

Musical Expressionism found its most natural outlet in opera, and the works of Alban Berg—specifically Wozzeck and Lulu—are considered the most outstanding examples of this style.1

In Wozzeck, Berg utilized a complex, highly emotional musical language to portray the protagonist's internal state. The opera employs extreme atonality, dense chromaticism, and traditional musical forms—such as the passacaglia and sonata—to create a work of profound psychological and dramatic impact. Critics at the time described the music as a "vision in sound," effectively capturing the chaotic and worried soul of the protagonist.2

Lulu, which Berg composed entirely using the 12-tone system, is similarly noted for being highly expressionistic in its idiom. Both operas demonstrate Berg’s ability to blend radical modern techniques with a deep sense of emotional content, using music to symbolize human existence and explore the depths of the human psyche.2