Dr. Kay Scarpetta finds herself in the unsettling pursuit of a serial sniper who leaves no incriminating evidence except fragments of copper. The shots seem impossible, yet they are so perfect they cause instant death. The victims appear to have had nothing in common, and there is no pattern to indicate where the killer will strike next. First New Jersey, then Massachusetts, and then the murky depths off the coast of South Florida, where Scarpetta investigates a shipwreck, looking for answers that only she can discover and analyze. And it is there that she comes face to face with shocking evidence that implicates her techno genius niece, Lucy, Scarpetta's own flesh and blood.