[4] Witch Week is set during the last four days of October 1981 at Larwood House, a boarding school in southern England, in a world parallel and close to ours.
This launches an internal investigation of the more unpopular students at the school (Nan Pilgrim and Charles Morgan), who are gradually coming to terms with the fact that they are witches.
Mayhem gradually ensues as magic is used to make birds appear in the classroom, to rain shoes, to curse a classmate into having his words always be true, and other pranks.
Four more of the students flee the school and two seek help from an "underground railroad" system that is known to save witches by sending them to a world where they are not persecuted.
Like many other books by Jones, Witch Week encourages readers to think for themselves and seek to make a positive change in the world.
Yet encoding and decoding is an area that Diana Wynne Jones tackles with great panache and hilarious humor in Witch Week (1982).
If one were to advertise the book by saying that she is drawing on theoretical concepts developed by Saussure, Foucault, and others, most readers would be discouraged, to put it mildly.
In fact Wynne Jones develops the text in such a way that the concepts are conveyed through a discourse which provides great fun for young readers, while also challenging adults to rethink some of the easily ignored yet problematic aspects of fiction-writing highlighted by recent theorists: Witch Week takes up matters such as the very nature of language as it functions via the arbitrary relationship between signifiers and what they signify, and so how we (mis)read a text; and the self-reflexive nature of a novel, as it plays with our presuppositions about how a fictional world relates to the one we are stuck with, especially as regards such seemingly inflexible features as its history and geography".
[5] Early in 1992, the science fiction writer Orson Scott Card reviewed reissues of several Diana Wynne Jones novels.
Thus it is that underneath what seems to be rather low comedy—brooms that demand to be taken riding by witches (and hoes and rakes and mops that can be ridden, but behave more like mules and pigs than noble steeds); prankster spells at about the level of magic spitwads—there is a continuous foundation of truth.
[7]: 155–156 In 2019, A. K. Larkwood, for Tor, wrote, "The casual horror of the totalitarian setting is introduced in mundane detail which disturbed me much more as an adult than when I first read it: 'bone-fires' are announced on the radio; almost all the characters’ parents have been executed or imprisoned.
[...] Reading again this year, I was struck by the fact that the characters of Witch Week save themselves in the end by finding help from other worlds, including one where witchcraft is practised freely.