In bestseller Barr s chilling 14th mystery thriller to feature National Park Service ranger Anna Pigeon (after 2005 s Hard Truth), Anna joins the team of Winter Study, a research project intended to study the wolves and moose of Michigan s Isle Royale National Park, the setting for 1994 s A Superior Death. Complicating the study is Bob Menechinn, an untrustworthy Homeland Security officer assigned to shadow the research. Crowded into inhospitable lodgings and persecuted by unrelenting cold, Anna is far from her comfort zone as nature turns awry with a series of bizarre events. The team stumbles upon the tracks and the mutilated victim of a preternaturally large, unidentified beast, and local packs of wolves descend on human-populated areas, a behavior out of step with their species. The campfire legends of youth metastasize into adult fears as Anna must piece together a connection between these anomalies while guarding herself from the strangers around her. Barr s visceral descriptions of the winter cold nicely complement the paranoia that follows the appearance of the mythic monsters at play.