Rendell returns to her favorite psychological-suspense device here: two separate story-lines that will eventually overlap--with fatal results. And, also as before (Lake of Darkness, Master of the Moor), Rendell's quiet English setting harbors a surprising, slightly excessive number of criss-crossing nut-cases. The principal plot focuses on the London-suburb household of mousey businessman Harold Yearman, whose wife has just died--leaving behind a strange, devoted pair of siblings: Dolly, in her 20s, a withdrawn innocent, psychically scarred by a large facial birthmark; and her teenage brother "Pup," short and insecure, who becomes bookishly obsessed with witchcraft, casting spells in his mini-temple upstairs. But then, while Dolly (a wine alcoholic, ever more disturbed) comes to believe utterly in Pup's abracadabra, Pup himself soon grows taller, discovers sex--and no longer needs the occult outlet. Will he, nonetheless, keep doing magic for Dolly's benefit? Yes, he will--because he loves her. . . and because his supposed witchcraft-club meetings give him a cover for his many amorous assignations. (Dolly is shocked, jealous, at each hint of Pup's sex-life.) So, when father Harold marries the youngish, vulgar Myra, Dolly persuades Pup to cast an evil spell on their "wicked stepmother"--who does indeed quite promptly die. (The real cause: a botched attempt at self-abortion.) This, of course, only reaffirms Dolly's faith in Pup's powers. And when Dolly's new, first-ever friend, lovely Yvonne, reveals that her husband is deep in a homosexual affair, wacko Dolly--now hallucinating like crazy, hearing voices --insists that Pup come up with a spell to kill off Yvonne's gay rival. But it's Dolly herself who finally does non-magical murder. . . unhinged by jealousy (Pup and Yvonne pair off), alcoholism, paranoia, and--when Pup won't magically remove her birthmark --bitter disappointment. Where's the second story-line, you ask? Well, Dolly will predictably meet her violent end from a neighborhood maniac--whose psychotic doings are dropped in now and again. And this contrived subplot is a significant flaw here. But, if less masterful than the best Rendell psycho-suspense (Judgement in Stone, Make Death Love Me), this is a strong improvement over Master of the Moor--with genuine, haunting creepiness and achingly pathetic irony in the central portrait: an obsessed brother and sister, one surfacing to sanity while the other sinks ever deeper into madness.