Among the post-war generation of children's writers none is more individual and more unpredictable than Diana Wynne Jones. Of her next book all one can be sure of is that it will be exciting, amusing and unlike the last. For one who treads the tricky paths of fantasy that is saying quite a lot.
In some ways the society shown in Witch Week is not unlike that of present-day England. Larwood House School is; in a nasty way, similar to other boarding schools. The pupils are not much more horrid than others; the teachers are odd, but then some of them are in real life. But something is wrong, as if we were looking at reality through a distorting glass. There is this preoccupation with witchcraft. And in an apparently civilized society witches, of all ages and both sexes, are burnt. With the Inquisitor ready to move in at a moment's notice, no wonder that witches and their probable fate occupy more than a fair share of the children's thoughts. (p. 231)
Miss Wynne Jones' favourite necromancer Chrestomanci comes to the rescue …, but not before we have had some pleasurable scares. The solution involves some explanations that belong to science-fiction more than fantasy.
Adults, who often find it more difficult than children to accept incongruities, may be bothered that so revolting a subject as death by burning can be treated in a funny way. I must admit that one or two things in this story stuck in my throat; on the other hand I also found myself laughing aloud, and that doesn't often happen. The invention, of character and incident (and the two are interlinked), is brilliant, the writing, and especially the dialogue, beautifully controlled. An offbeat masterpiece. (p. 232)
Marcus Crouch, in his review of "Witch Week," in The Junior Bookshelf, Vol. 46, No. 6, December, 1982, pp. 231-32.