'Blood Work' - that's what Terry McCaleb used to call his job at the FBI. Eight weeks ago he was a dead man, but now someone else's heart is keeping him alive. When McCaleb discovers that he lives because of a cold-blooded murder the ex-FBI investigator is forced back on to the streets. The police investigation is going nowhere fast and there are few clues to fall back on. But as McCaleb puts together the evidence of a crucial witness with the gut instincts sharpened by a career spent hunting down serial killers, the killing looks less like a random shooting and more like the first move in a calculated campaign of terror.