Having combed the streets of modern-day Paris for carriers of the bubonic plague in the idiosyncratic policier '' Have Mercy on Us All '' -LRB- translated from the French , as is this new one , by David Bellos -RRB- , Fred Vargas 's appealing flic returns in SEEKING WHOM HE MAY DEVOUR -LRB- Simon & Schuster , paper , $ 14 -RRB- to investigate a series of savage attacks attributed to a werewolf that crossed the Italian Alps into Mercantour National Park and is now cutting a bloody swath through the French countryside .