Ngaio Marsh 
Spinsters in Jeopardy [EPUB ebook] 

A British police detective looks into sinister doings in the South of France in a crime thriller with “more than a little excitement” (Kirkus Reviews). Inspector Roderick Alleyn has decamped for the South of France on a family vacation—though for him, the vacation will involve some official poking around. Unfortunately, the object of his poking—the cultish denizens of a sinister and luxurious chateau—are not fond of being poked, and they have a particularly unpleasant way of getting their point across . . . “Charming, cultivated, witty—and none the less terrifying . . .a pure thriller . . .you’re not apt to find a better evening’s entertainment.” —The New York Times