The Bishop would like to give Countess Kussmaul, a patron and great lover of Mozart's music, one of Amadeus' compositions as a birthday gift. Devilius bets the Bishop that Amadeus cannot deliver a piece in such a short time. Confident of Mozart's talent as a composer, the Bishop wagers half of his royal household. In an attempt to win the wager, Devilius and Monti the Rat devise a villainous plan.