The Spook's Mistake is the fifth book in Joseph Delaney's terrifying Wardstone Chronicles - over 3 million copies sold worldwide! 'The moment of danger is close. Very soon our enemies will be here.' The Spook has sent his apprentice, Tom, to be trained by another Spook whose methods are harsh and tough. But faced with a powerful water witch, Bill makes a fatal error, leaving Tom to face his enemies alone. Can the Spook get there in time to save his apprentice? Or will his own mistakes give final victory to the dark? From the series that inspired the forthcoming movie Seventh Son, starring Jeff Bridges, Ben Barnes and Julianne Moore.