Ghost stories are usually about repression. In the 19th century the thing being repressed was sex; in Waters' version of the late 1940s it's something else, but I can't say what exactly for fear of giving the game away. The Little Stranger is not only a ghost story but a whodunnit- and Waters is as adept as Christie (whose territory she impinges on- mysterious happenings in an isolated great house) at hiding crucial information in plain sight. She writes with wonderful clarity, an eye for the telling image and a profound understanding of the vagaries- the overspilling messiness- of human nature. Her characters draw you in and implicate you in their unpleasantness .It took me hours after turning the final page to shake off my feelings of guilt.