Rock'n'Roll and bananas has arrived the country, and Egon has found out about sabotage plans about a circus, in order to take it over.
A fiendish conductor takes over a school band. She eliminates five musicians who then form their own ensemble. With the help of their former conductor, the new band enters The Norwegian Championship against their old band.
Hearing about the Kings Jewels hidden deep in a silver mine, the Junior Olsen Gang embark on a thrilling hunt to prevent the Jewels from landing in the wrong hands.
