Now thirteen years old, Tom Ward continues his apprenticeship with the Spook as they confront a dangerous bane who can control people's thoughts.

When witches steal Tom's inheritance and kidnap his relatives, Tom, the Spook, and Alice set out for Pendle Hill, a particularly dangerous district, in hopes of preventing the three witch clans from uniting to raise the Fiend, the Devil himself, thus bringing about an age of darkness.

Tom is reunited with his mother and must return to Greece to face a new and terrible threat from the dark forces, and a momentous decision must be made, causing a serious rift between Tom and the Spook that threatens to separate them forever.

Apprentice Tom and the Spook for whom he works flee to Ireland, where a powerful witch has joined forces with the dark mages trying to call forth ancient powers to destroy Tom.

As creatures of the dark hunt for the witch assassin Grimalkin, who carries the captured Fiend's head, Spook's apprentice Tom tries to find a way to finish this terrifying evil once and for all.

"Alice Dean's destiny is intertwined with Tom Ward's. But he's going to be the next Spook, and she's a witch--possibly the most powerful one the county has ever seen. To rid the world of its greatest evil, the Fiend, Alice will venture into the depths of the dark"--