The killer's methods are terrifying. He stalks the basements and underground passageways of New York City. He tattoos his victims' flesh with cryptic messages, using a tattoo gun loaded with poison, resulting in an agonizing, painful death. When a connection is made to the Bone Collector, the serial killer who terrorized New York more than a decade ago, Lincoln Rhyme and Amelia Sachs are immediately drawn into the case.