Sweden 1958. In a small provincial town there is a band who plays dance music twice every week. All decisions are made by Sven Klang, the undisputed leader of the band. A new member joins them, saxophone player Lasse. He starts to criticize Sven's decisions, questions the way they divide the money and he also wants them to be more of a jazz band.

The youngest princess is the king's darling daughter. One day she wants to have the three singing leaves. The king intend to make it happen. The leaves are owned by Prince Hatt under jorden.