This was a slow starter but definitely twisted once it got going. This ia a hardcover copy of this book.

From Publishers Weekly
Readers fearing that recently retired FBI Agent E.L. Pender (The Girls He Adored; Fear Itself) would devote himself to a life of leisure on a sandy beach can breathe a sigh of relief: his serial killer hunter skills are as sharp as ever. Pender does head for a tropical isle, though-the fictional St. Luke in the U.S. Virgin Islands-when old pal Julian Coffee, the chief of police, invites him to help hunt down a sadistic killer whose signature is severing the right hand of his many victims. The identity of the killer, or in this case killers, is no secret to the reader: kinky anthropologist spouses Phil and Emily Epps are shown early on murdering St. Luke resident Andy Arena after a "sadomasochistic tango." The Epps believe that sucking in a dying person's last breath will make them all-powerful, a ritual learned on one of their field expeditions. Drawn into the Epps's cabal is narcissistic Lewis Apgard, scion of one of the island's founding families. Lewis needs to have his wife, Hokey, killed so he can move forward with a land scheme that will net him big money, and fortunately for him, the Epps are glad to help him out. Meanwhile, Pender, "bald and homely as a boiled potato," finds love with a beautiful local lady who has a serious law enforcement problem in her past. Nasaw is such a clever writer that it's hard not to root for all his quirky characters, including the Epps, though we're constantly reminded that the deadly duo is bad, bad, bad. Even so, Nasaw is able to whip up plenty of suspense as Apgard and the Epps take Pender prisoner, grab a child hostage and make one last bid for freedom.