Often-serious veteran Guthrie (The Big Sky) enjoys his holiday entertainments, little riddle novels that skitter and fritter--and this likable but woolly-minded Montana conspiracy-and-murder tale is one of them. Midbury, Montana, is in the grip of a 40Ã˜-below cold snap that is bogging down the beginning of a big strip-mining operation in the area. Land-proud ranchers (who oppose the mining) are squaring off against work-hungry coal miners--and feelings run high in town at the two bars polarized by the opposing factions. Caught in between: Sheriff Chick Charleston, a thoughtful, hayseed Sherlock with a college-senior sidekick, Jason Beard (with whom he trades effortful literary associations). And Chick and Jason have their work cut out for them when cattle start turning up with their rectums and genitals and udders missing as if eaten by wolves; there's something fishy about these carcasses, whose brands are missing. Plus: the half-owner of the miners' hangout (""The Chicken Shack"") is found shot to death by a bizarre bullet. A barfight, a wife-beating, attempted buying of the sheriff by the mine operators, and another death (of the accidental ""murderer"") by a senile loon, along with the exposure of some phony wolf packs--all this makes for a tale whose wayward plotting is almost redeemed by the slice-of-life realism of characters and setting.