Kearney and Phelps are certain the killer will strike again and know they're working against time. Using the best evidence modern forensics and computer science can supply and the good guesswork 25 years of homicide investigations have sharpened, they begin to see some patterns, but not enough to connect up the dots. Then the finger of one of the victims is found sealed inside a plastic baggie in a raided crack house. Cutting corners, pulling in favors, they track the evidence back to what they believe will be the killer, only to find he is one step ahead of them. In a climactic nightmare chase, Kearney races to save the person dearest to him as he faces off against a cunning homicidal maniac.