Tiffany Aching is the witch of Chalk, which means that she has to do all the messy rural stuff that witches do. But witches aren't always as appreciated as they should be, and Terry Pratchett's "I Shall Wear Midnight" flings the sensible young girl -- and the Nac Mac Feegles -- against a threat that really, really doesn't like witches. 
 Tiffany is doing the usual witchy rounds in Chalk -- nursing the sick, burying the dead, watching cheese races, and rescuing the occasional girl from an abusive father. Then the local Duke expires after a long illness, and it's up to Tiffany to tell his son Roland and his "watercolour-painting wife-to-be" about what happened. 
 The problem is, she's being stalked by a creepy eyeless man with a vile psychic stench, who is inspiring people to hate and distrust witches. Suddenly stones are being thrown, accusations are being made, and Tiffany even finds herself in the Ankh-Morpork jail. And if Tiffany doesn't find a way to stop the Cunning Man, things will get very toasty for the witches... 
 Due to having Alzheimer's disease, Terry Pratchett had to dictate "I Shall Wear Midnight" instead of the usual computer typing. As a result, the book's beginning is very rambly and scattered, as if Pratchett hadn't fully thought out how the plot was going to go -- but after the Duke's death, things start to tighten up and move faster. 
 And Pratchett hasn't lost any of his delicious wit, whether it's poking fun at cliches (the cackle box!) or sharp dialogue ("Have you boys got no shame?" "I couldnae say, but if we have, it probably belonged tae somebody else"), or his knack for writing truly chilling moments, such as Tiffany seeing the Cunning Man's holes-where-his-eyes-should-be, or the almost palpable darkness as hatred starts to take over people's hearts. 
 But unlike authors who talk down to "young readers," Pratchett doesn't shy away from realistically dark moments, like Tiffany caring for a girl who was badly beaten by her father until she miscarried. These parts -- and the "rough music" -- are more horrifying than the Cunning Man. 
 Tiffany herself is a very realistic depiction of a sensible, mature, no-nonsense young lady (like a younger version of Granny Weatherwax). While Pratchett occasionally reminds us that she IS still young (and prone to little stabs of jealousy), she grows up a great deal in this book. And there are some hints of romance with a young guard (who can pronounce the word "marvelous"). 
 "I Shall Wear Midnight" is an excellent penultimate entry in Terry Pratchett's Tiffany Aching series. It starts out rather slow, but soon kicks into stride.