Tom and Jamie return to Dino World with a new mission: prehistoric "wildlife watching". They've learned how to camouflage themselves to see animals back home, so why not dinosaurs, too? Up in a tree, hidden by mud and leaves, Tom and Jamie spot a friendly plant-eating diplodocus. But Dippy gets hostile when a branch becomes lodged in his gums. In order to help this hurting herbivore, Tom and Jamie will have to become dino dentists!