Pratchett Terry. Discworld 32. A Hat Full of Sky

Incipient witch Tiffany Aching, who confronted danger in The Wee Free Men (2003), faces even greater peril in this equally quirky sequel. She is taken on as an apprentice witch by Miss Level, who is one person with two bodies-an oddity to say the least. Also, Tiffany is stalked and taken over by a hiver, an invisible, brainless entity that commands and distorts the mind of its host, which eventually dies. Luckily Tiffany is strong enough to hide a section of her mind within herself, but she is otherwise completely under the control of the hiver. It's the cantankerous Wee Free Men (or the Nac Mac Feegle) to the rescue, with the help of Miss Level and the wisest, most respected witch of all. The chase is part slapstick, part terror, and in the end, Tiffany herself sets things straight. Pratchett maintains the momentum of the first book, and fans will relish the further adventures of the "big wee hag," as Tiffany is known to the Feegles.