Ali McGovern, the mentally unstable narrator of this unsettling thriller set in Scotland from Edgar-finalist McPherson (Quiet Neighbors), manages to land a well-paying job at Howell Hall, a psychiatric hospital in the Galloway countryside, despite her lack of experience with special-needs clients. On the home front, her husband has run his business into the ground, and her beloved 15-year-old son is sullen and uncommunicative. At Howell Hall, Ali develops a fondness for Sylvie and Julia, two young patients, but can't figure out why they've been confined there. Nor does the director provide satisfactory answers to Ali's questions. The discovery of a body on the hospital grounds increases her anxiety. In this universe, no one is to be trusted, and Ali is forced to rely on herself-despite all the questions about her own tenuous grip on sanity. McPherson keeps the suspense level high; her heroine comes across as clinically interesting but not particularly sympathetic.