Trixie convinces the kids to follow her into an old, creaky castle that is haunted by Robbie Rotten!
It's snowing in LazyTown, and all the kids want to have fun outside. Robbie disguises himself as a snow monster to frighten the kid back indoors.
The kids decide to put on a circus. But before long, Ringmaster Robbie tries to shoot Sportacus out of LazyTown in a cannon.
Robbie poses as a teacher at the LazyTown school so the kids will stop learning new things. The during chemistry class, Robbie causes a chemical reaction that might blow up the whole school. Can Sportacus stop the reaction and save the day?