'Anne! Come down at once. He's gone,' shouted Dick. 'Hurry!'

It's half-term and the Five are going hiking through the woods and up the hills. But when Anne and Dick take a wrong turn, it leads them all straight into danger! An escaped convict is on the loose and passes a strange message to Dick by mistake.

A stash of treasure has been hidden nearby - will they discover it before the prisoner strikes again?