Trolls on Hols

It's summer, and all of Ulrik's school friends seem to be going on something mysteriously called 'a holiday'. His parents, Mr and Mrs Troll, investigate. Their neighbours, the Priddles, have just bought a caravan, and after a muddled conversation, it seems the troll family have been invited to join them. But when they arrive at the campsite and the Priddles discover their caravan is full of trolls, they don't seem very pleased. And incredibly, things get even worse, with stories of a large sheep-devouring best on the loose near the campsite and a mystery for Ulrik to solve.