Anna Bronsky is a violin teacher at a music-focused high school. Despite the opposition of all other teachers, Anna drives through the admission of a student, Alexander, in whom she detects a remarkable talent. Committee, she prepares him for the intermediate exam and neglects her family, her son Jonas, who she brings into competition with her new student, and her husband Philippe. Her colleague Christian, with whom she has an affair, persuades her to join a quintet.