An unidentified nude female sits propped against a fountain in Central Park. There are no signs of struggle. When Dr. Kay Scarpetta and her colleagues Benton Wesley and Pete Marino arrive on the scene, they instantly recognize the signature of serial killer Temple Brooks Gault. Scarpetta, on assignment with the FBI, visits the New York City morgue on Christmas morning, where she must use her forensic expertise to give a name to the nameless--a difficult task. But as she sorts through conflicting forensic clues, Gault claims his next victim. He has infiltrated the FBI's top secret artificial-intelligence system developed by Scarpetta's niece, and sends taunting messages as his butchery continues, moving terrifyingly closer to Scarpetta herself.
Upon examining a dead woman found in snowbound Central Park, Kay Scarpetta immediately recognizes the grisly work of Temple Gault, a bold and brilliant killer from her past. Now she must hunt down a psychopath whose string of horrible murders is leading inexorably to his ultimate prey: Scarpetta herself. Even with the help of the FBI, Scarpetta knows the endgame is hers alone to play -- and it will be played on Gault's home turf, the subway tunnels beneath New York City.