The Robinson’s are getting a new sofa, and Dad and Mr Shah are trying to move the old one. It is so big and heavy, they need to use all their strength to carry it. Once the old sofa has been moved, Biff, Chip and Nadim are excited to discover lots of things in the space where it used to be. They even find a lost action figure: Cavegirl. Chip remembers that Cavegirl used to have two special friends, and so the children go on a quest to reunite Cavegirl with her companions. Their imaginative journey takes them to the top of a fiery volcano and through a freezing ice-world. But before they can safely return Cavegirl back to her cave, they come up against the biggest obstacle of all: the old sofa blocking their path! Dad and Mr Shah have managed to get it wedged in the hallway, and they need to shift it before the new sofa arrives. What are they going to do? Luckily, Biff realises that Cavegirl and her friends might just have the answer.