A small mountain community in the French Alps is roused to terror when they awaken each morning to find yet another of their sheep with its throat torn out. One of the villagers thinks it might be a werewolf, and when she’s found killed in the same manner, people begin to wonder if she might have been right. Suspicion falls on Massart, a loner living on the edge of town.
The murdered woman’s adopted son, one of her shepherds, and her new friend Camille decide to pursue Massart, who has conveniently disappeared.
Their ineptness for the task soon becomes painfully obvious, and they summon Commissaire Adamsberg from the city to bring his exceptional powers of intuition to bear on layer upon layer of buried hatred and secrets.