Fred Marsac built his life around jazz. He was happy with his family, alongside his wife and two children, Estelle and Sam. When his wife died in a car accident, he disappeared. He entrusted Sam and Estelle to his in-laws, only to reappear four years later. The welcome is frosty. Estelle rejects him, and his in-laws resent him. To redeem himself, Fred accepts a position as a music teacher at a middle school. The principal, Isabelle Martinet, reluctant to integrate him into the teaching staff, assigns him the most difficult class.