In this latest novel from bestselling author John Verdon, ingenious puzzle solver Dave Gurney puts under the magnifying glass a notorious serial murder case – one whose motives have been enshrined as law-enforcement dogma - and discovers that everyone has it wrong. The most decorated homicide detective in NYPD history, Dave Gurney is still trying to adjust to his life of quasi-retirement in upstate New York when a young woman who is producing a documentary on an infamous murder spree seeks his counsel.  Soon after, Gurney begins feeling threatened: a razor-sharp hunting arrow lands in his yard, and he narrowly escapes serious injury in a booby-trapped basement.  As things grow more bizarre, he finds himself reexamining the case of The Good Shepherd, which ten years before involved a series of roadside shootings and a rage-against-the-rich manifesto.  The killings ceased, and a cult of analysis grew up around the case with a consensus opinion that no one would dream of challenging—no one, that is, but Dave Gurney.      Mocked even by some who’d been his allies in previous investigations, Gurney realizes that the killer is too clever to ever be found.  The only gambit that may make sense is also the most dangerous—to make himself a target and get the killer to come to him.