While Harry plays on the beach, making sandcastles with his new bucket, he comes across a shell that would make the perfect castle decoration. Harry and the dinosaurs are startled when the shell scuttles off towards a tide pool. As the gang investigate the tide pool, Harry decides that he would love to explore this magnificent world some more, and so he goes into his regular bucket to Dino World to do just that. A fun adventure is had by all and they even come across a familiar creature, in need of a new home, before returning to Nana to explain why the new bucket is missing.