The winner of the waltz competition will gain Tanya's hand. The King is confident, of course, that Allegro will win. Tanya, however, has fallen in love with Johanne, a poor composer, and she persuades him to enter a waltz of his own. Allegro, afraid of being defeated, has the-two manuscripts changed over and when Johanne's "Enchanted Waltz" is hailed the best at the Court, Allegro claims it for his own. However, through the intervention of Queen Titania and her fairies, matters are righted and the wicked Master of the King's Music is made to confess his trickery before the King, while Johanne is given Tanya's hand.