Ludwig van Beethoven tries his best to raise his troubled nephew Karl, thinking Karl’s mother, Johanna, is unfit. Predictably, Johanna feels the same way about Beethoven.
The Maestro begins with Karl van Beethoven greatly at odds with his uncle, the famous composer Ludwig van Beethoven. Stephan von Breuning, a long time friend of the composer, invite Karl to visit him at his law office in order to talk to Karl and help his relationship with his uncle. Yet Karl is at his wit's end dealing with his controlling uncle and does not want to talk to Stephan, thinking that Stephan will simply tell Beethoven everything he says. As Karl get up to leave a note leaves his pocket. Stephan picks it up, but before he can read it, Karl rushes to get it from him. Stephan hands it over, but Karl ends up staying at his office. He says that he will allow Stephan to read the letter if he tells him about his uncle. Although reluctant at first, Stephan agrees. Detailing Beethoven’s traumatic childhood, his virtuoso performances in Vienna, his lost loves, inexplicable deafness, and the custody battle with Karl's mother Johanna, Karl comes to better understand his uncle. After talking with Karl, Stephan tries to tell Beethoven that he should be more understanding toward Karl. Soon, the start of a smoother relationship begins to emerge. Beethoven, a noble but quick tempered person, tries to be more patient with Karl but this is short-lived. The old antagonism in their relationship emerges and they have an argument which leads Karl to attempt suicide. Beethoven is shocked and grief-stricken by this act of desperation. His already troubled health takes a turn for the worst. Yet ultimately Beethoven reconciles with Karl and Johanna before he succumbs to his final illness.