The protagonist, a boy called Paul Crabbe, is taught piano by his teacher (or maestro), Eduard Keller. Paul does not like his teacher at first, but by the end of the novel has grown to appreciate him dearly. Paul learns the limits of his own musical ability through Keller, but he also grows to understand himself and Keller enough to write the novel. Additionally, he has a loving relationship with his sweetheart, Rosie.
This book deals with the main idea of contrasts, as well as other themes. Contrasts are shown by Paul's mother and father how they differ; Vienna and Darwin high culture vs. low culture; Paul as an adolescent and Paul as an adult through the continual change in narrator, as Paul changes.
The most influential character, Eduard Keller, lost his family during The Holocaust, despite performing for Adolf Hitler in private concerts in the belief Hitler would spare his Jewish family.
Peter Goldsworthy's novella Maestro is based on adolescence and growing up. Keller (the Maestro) educates Paul about the basis of life through music metaphors and Paul learns of other cultures and lives through Keller's experiences in Vienna. The book follows Paul from early adolescence into adulthood and depicts Paul learning and understanding about life.
For Keller, the grand piano is his sanctity and security, assisting him to deal with the horrors of the world; "safe beneath that grand piano," and likewise offering Eduard a method of destructing life. "Never trust the beautiful beauty simplifies" quotes Keller referring to music, also relating to the world. Goldsworthy typifies beauty as a faade, a means of avoiding reality, depicted by Paul's discovery of true love in Rosie, whom he initially dismissed as "podgy baby-fat" and "mousy" as he lusted after Megan. As Paul matures, Keller's phrasings, which seemed absurd in adolescence, hardened into a "musical bible whose texts I knew by heart" but Paul does not relate them to his life until middle-age, leaving him "smug, insufferable," throughout his life.