As sixty-year-old John Gregory reflects on the past, he reveals how the world of ghosts, ghasts, witches, and boggarts was exposed to him and he later became the Spook, even though his first intention had been to join the priesthood.

Ready to be presented to the last apprentice, Tom Ward, the spook's notebook contains instructions for vanquishing boggarts, witches, the unquiet dead, and other dark creatures and spirits.