Peter, Paul, and Heinz have been best friends since early childhood; the first two are treated almost like Heinz's own children by his parents, Mr. and Mrs. Liebitz. One day, a terrible accident occurs during a regatta: Heinz falls into the water and drowns. Despite this horrific event, the bond between Mr. and Mrs. Liebitz and Paul and Peter only intensifies. The elder Liebitz owns a musical instrument manufacturing business, and since Heinz will no longer be able to take over the company as originally planned, Franz Liebitz comes up with the idea that Peter and Paul should run the business instead. The two young men receive training in instrument making, but they don't want to become dependent on him and decide to earn their living by repairing instruments and/or as music teachers.