Styled as the memoir of a famous composer named Kuhn, Gertrud tells of his childhood and young adult years before it comes to the heart of the story; his relationships to two troubled artists, the eponymous Gertrud Imthor, and the opera singer Heinrich Muoth. Kuhn is drawn to Gertrud upon their first encounter, but she falls in love with and marries Muoth, whom the composer befriended as well some years before.