Roberts's (Pawns) mystery novel generates suspense, but, ultimately, too many unanswered questions will leave readers unsatisfied. Eight months after 14-year-old narrator Nikki's mother dies, her father marries Crystal, a younger woman. On a picnic to meet the kids, shy Crystal admits to a tragic childhood (her parents both died when she was seven), and when she later inherits a beach house from her aunt, she unsuccessfully resists Nikki's father's decision to vacation there. Nikki's father must return home, and leaves Crystal in the beach house with the kids. The woman begins to act strangely. Crystal has nightmares, forbids Nikki to go to the neighboring mansion of a handicapped professor, who has hired the girl to type his manuscript, and hides her hair in public. Nikki must decide if Crystal is merely "sensitive" or if something larger looms. Many of the chapters have cliffhanger endings ("And that was when everything seemed to start falling apart"), and the big old houses overlooking the ocean provide a solid setting for the plot to unfold. But while the mystery surrounding Crystal's behavior is finally solved, others are not, both small (What's important about Crystal drinking so much carrot juice?) and large (Why doesn't anyone in town tell Nikki why the mansion is supposedly haunted?). This, compounded by cookie-cutter characters, such as the matronly housekeeper and creepy gardener (even Nikki herself is a bit too formal, and her relationship with the professor's son is weak), makes for less-than-scintillating sleuthing. Ages 8-12. (Mar.)
