Who says there's nothing doing along the banks of the Snake River in summer? When John Denson and his partner Willie Prettybird, the Cowlitz shaman, arrive in Enterprise, Oregon, the town's gearing up for a triple celebration: Chief Joseph Days, an annual commemoration of the great chief's surrender; Enterprise High School's reunion, which has attracted such famous alums as Rev. Thaddeus Hamm Bonnerton, class nerd turned ecological preacher; and Rev. Thad's earth-scrubbing, money-grubbing Bible crusade. But Denson and Prettybird (Bigfoot, 1993, etc.) are in town on more somber business: Somebody has killed state trooper Dave McAllister on embattled rancher Monty Hook's spread, and Denson can't help connecting the murder (and another one that's still around the bend) to a deadly outbreak of anthrax, equally dangerous to four- and two-footed animals, among Hook's livestock. Application of Prettybird's theory of the Great Hoop (``what goes around comes around'') tells Denson who the culprit is, but not how to contain the disease before it rages into a full-blown epidemic. The eco-disaster scenario, perhaps borrowing its urgency from Hoyt's recent international thrillers Red Card (1994) and Japanese Game (1995), sits oddly atop the laid-back crew of northwestern eccentrics Hoyt knocks off as well as anybody around.