When Toby Jugg, Measle's nemesis, turns up on the school trip, Measle knows he's in danger. The school trip is supposed to be an adventure and a challenge - and now it is. Toby Jugg shoves Measle into a dark hole - the doompit, a door to all sorts of scary worlds. Measle must escape the jaws of a pack of werewolves, the pincers of some giant ants, the massive arms of the abominable snowman, and the petrifying stare of the gorgon. Oh, and rescue his schoolmates, find Iggy and Tinker, discover a way out and defeat Toby Jugg at the same time. Thank goodness Measle is one of the bravest boys around!