Laurels are Poison (1942)
My review:
"'Is it a dagger that I see before me, its 'andle to me 'and? No, but it is that same circular saw with which Hawley Harvey carved up his spouse, et voici la plume de ma tante. Goroo! Goroo! (Dickens—or thereabouts.) Stop me if you've heard it before. Young Alice, there must be a murderer on the premises!'"
This is Mitchell's own favourite among her novels, because it "recalls the college years which I enjoyed so much." Certainly, she seems to be having a ball—the tone is very high-spirited, the humour a brilliantly funny mixture of farce and wit, and the dialogue of Laura Menzies (introduced here as a young woman studying to become a teacher) is a pleasure. The training college setting is vividly evoked, so that the reader receives an impression of what such an establishment would have been like, and Mrs. Bradley ("with degrees from every University except Tokio") is in fine form as the Warden of a House. The plot is inventive, mixing the high-spirited with the macabre, and involving such things as disappearing Wardens, a fatal accident in a school gymnasium, rags (both stupid practical joking, and malicious attacks / vandalism), a ghost, a drowned cook, and human skeletons. The exposition of the murderer's identity and motive in the penultimate chapter is, as Philip Larkin pointed out, eerie and bizarre—Swinburne's "Itylus" is used to great effect.