The Astounding Treacle Tree

The Treacle Tree, who lives outside Dr. Snuggles' house, is bored of staying in one place. Seeing the birds gives him the idea that he wants to learn how to fly. Dr. Snuggles builds him a pair of wings, but when the tree goes missing on his practice flight, the gang has to go look for him in Dr. Snuggles' space rocket.