When Vermont recluse Abraham Fuller dies, the autopsy reveals he was killed by an aneurysm--caused by a bullet shot at him about 20 years before. Back at the dead man's house, Brattleboro police lieutenant Joe Gunther (Scent of Evil, etc.) discovers that an elaborate astrology chart and a copy of The Scarlet Letter are missing, and also that there's a body buried deep in the garden- -dead about 20 years, with a surgically implanted stainless-steel knee joint. Who was the dead man and what happened? Joe tracks the knee joint to Chicago, where with the aid of about-to-retire cop, Norm Runnion, he's soon stirring up aging radicals who supported the Chicago 8--and stole millions in donations that were earmarked for their defense. A surgeon will die and Joe will be gulled by suspects and befriended by mobsters before the trail leads back to Vermont, where, give or take a name change or two, he identifies the principles in this decades-past story, which culminated with a wild gun chase during Vermont's grand tourist attraction, the Bread and Puppet show. Crisp medical writing and an intriguing premise don't quite obscure two major plot holes, one involving motivation and the other a misinterpreted clue. Mayor, who could probably write dandy investigative nonfiction, needs to tighten up his storylines before this otherwise estimable series sinks into mediocrity.