It is the day before Karl, an apprentice clockmaker, is supposed to unveil his personal addition to the great clock tower in Glockenheim. But despite the intense anticipation of his master and the townspeople, he has created nothing, and the next day will be a day of humiliation rather than triumph. A sinister figure steps right out of the story that Fritz, a local storyteller, is relating to his audience and offers Karl a clockwork knight so exquisitely wrought that it looks almost real. The trouble is that the knight will seek out and kill anyone who utters the word ‘devil’, and Fritz, who began this story, has not worked out how to end it. However, once a story has been wound up, it must continue ticking to the end. Will Karl sell his soul to the devil and accept the deadly knight to get him out of trouble? The implications of his actions have terrifying consequences for Gretl, the brave daughter of the innkeeper, who tries to save the young prince whose clockwork heart is winding down. Like all good folk tales, this story has suspense, terror, tragedy and a magical ending.