At the start of this highly readable if predictable third thriller by Lashner (Hostile Witness; Veritas), Philadelphia lawyer Carl answers the late-night distress call of his friend Guy Forrest and finds him naked and sobbing on the front steps of a suburban house. Inside is the corpse of Guy's lover, Hailey Prouix, the woman for whom he left his devoted wife and kids. Even though at first he's unconvinced of Guy's innocence, Carl eventually agrees to represent Guy when he's charged with murder. Carl also holds an important secret that he keeps from Guy; from his own legal partner, Beth; from everyone, in fact, but the reader: Carl was Hailey Prouix's lover, too. In the novel's early chapters, Lashner effectively describes the mind games that Carl plays with himself, rationalizing decisions that are in his own best interest, if not those of his client. Once he believes Guy's earnest claims, Carl begins to probe Prouix's past, more to answer his own nagging questions about her than to find her killer or even to save Guy. The trail takes him to Las Vegas and to Prouix's childhood home in West Virginia. The past sins and crimes that Carl uncovers are of the predictably unspeakable variety. Indeed, the plot has a by-the-numbers feel: in one set piece, Carl is pursued and run off the road by a mystery car with tinted windows. What raises Lashner's thriller above the ordinary is its rich and resonant first-person narrative. Since his debut in 1995's Hostile Witness, the character of Carl has aged like fine wine. His wit is sharper and deeper now, but he also displays a bittersweet nostalgia and a more seasoned (if jaded) worldview. He's a provocative and entertaining guide, far more entertaining than the journey on which he leads us. 6-city author tour. (May 16)