The five friends George, Julian, Dick, Anne and Timmy the dog, go for the first time together on holiday. Without parents they set out on a bike ride that takes them into the legendary Cat Canyon. Already at the first bonfire siblings George and Dick make her friends fear and tell the story of the 'Black Cat'. According to legends a thief should have hidden the largest diamonds in the world, the green emerald in the Cat Canyon. And a few seconds later comes a figure out of the bushes. It is the small Hardy who lives in the area and has nothing better to do than to show off his phone and his quad. Although they become friends soon.