Like so many of Patrick McGrath’s narrators, Dr. Peter Cleave is reasonable, likable — and absolutely unreliable. A psychiatrist at a maximum-security asylum in rural England, Cleave recounts the story of an affair between Stella Raphael, the wife of the deputy superintendent, and Edgar Stark, a patient of Cleave’s who murdered his wife with a hammer. Her id stripped bare for all to see, the lovely Stella confounds polite society as she descends into madness and reveals the narrator as a self-serving autocrat who plays God with his patients. McGrath’s first novel, The Grotesque, will hit the big screen this year (retitled Gentlemen Don’t Eat Poets and starring Sting and Theresa Russell), and Asylum was recently optioned by Paramount. But don’t wait for the movie: This is a cleverly insidious, beautifully rendered thriller with just the right balance of splatter and innuendo.