At the start of Thriller Award–winner Deaver’s stellar 14th Lincoln Rhyme novel (after 2017’s The Burial Hour), William Sloane and Anna Markam, an engaged couple, enter the jewelry store of Jatin Patel, a master diamond cutter who works in Manhattan’s diamond district, to pick up a ring. Unfortunately, a gunman wearing a ski mask is right behind them. After the intruder shoots William and Anna dead, he tortures and kills Jatin with a box-cutter. Vimal Lahori, an employee, arrives at the store, takes a shot in the side from the killer, and manages to escape. Rhyme and his usual team—Det. Lon Sellitto of the NYPD, lover Amelia Sachs, patrol officer Ron Pulaski, and lab expert Mel Cooper—investigate. The tension rises as Vimal tries to stay hidden, the killer hunts more victims, and the media receive a note from “The Promisor” threatening the deaths of more engaged couples. Deaver keeps the twists and surprises coming in this roller-coaster ride of a thriller. Five-city author tour. Agent: Deborah Schneider, Gelfman Schneider Literary Agents. (Apr.)