Hilda and Twig would never let a bit of rain get in the way of an adventure, but it's different when your forest exploration is interrupted by a BIG storm. Sheltering in a mysterious mound in the earth, Twig quickly realises that trouble is afoot, and that his best blue-haired friend is in danger. Unfortunately, he's never really thought of himself as the brave one, but it looks like he's going to have to step up and save Hilda from a whole load of big, scaly trouble!