The Cold Moon by Jeffery Deaver

On a freezing December night, with a full moon hovering in the black sky over New York City, two people are brutally murdered -- the death scenes marked by eerie, matching calling cards: moon-faced clocks inves-tigators fear ticked away the victims' last moments on earth. Renowned criminologist Lincoln Rhyme immediately identifies the clock distributor and has the chilling realization that the killer -- who has dubbed himself the Watchmaker -- has more murders planned in the hours to come.