Moon Baby, Pepi Nana and their friends discover a toy roundabout left in the Toy House. Moon Baby uses his story magic, and the roundabout transports everybody to an adventure in Storyland, where Mr Onion rescues Dibillo's balloon from a tree.

The discovery of a nursery rhyme book in the Toy House inspires Mr Onion to play at being Humpty Dumpty. When Humpty Onion refuses to fall off the wall, all the Toy House friends join in a game to make a comical new ending to the Humpty rhyme.