Book two of Fred Vargas's 'Commissaire Adamsberg' series of murder mysteries is Seeking Whom He May Devour set, not in or around Paris, but in the Mercantour National Park in the Alpes-Maritimes region of southern France.
Naturalist, Lawrence Johnstone, a Canadian, is studying wolves in the Mercantour NP and is finding it hard to leave the area despite his work being finished. Partly he's come to love the region and the wolves but also he lives with a lovely young French woman, Camille, and does not want to leave her. Coincidently she is also an ex-girlfriend of Commissaire Adamsberg's. The two live in a small, very rural, village, Saint-Victor-du-Mont, where everyone knows everyone else intimately and also their business.
A number of ewes belonging to a local farmer, Suzanne Melchior, are found brutally killed and a few days later so is the farmer herself. Johnstone tells Camille that Suzanne had told him confidentially she thought there was a werewolf on the loose and that she thought a local by the name of Massart was a likely candidate. It seems crazy but the sheep and the farmer have definitely been killed by a very large wolf, not a dog or any other kind of wild animal.
Massart disappears and they find a map that he's marked with a rural route up across France to England where he has a relative living. Johnstone suggests that Camille and two others, Suzanne's adopted son Soliman and her shepherd, Watchee, drive after him in a dilapidated old lorry. It's a cat and mouse chase they embark upon, but the mouse is always one step ahead. They need help and Camille remembers her ex-boyfriend, Adamsberg...
Great fun. (If you're allowed to say that about a story about vicious murders.) I loved the banter and cameraderie between Camille and her travelling companions, what a couple of characters! And the region is really brought alive by Fred Vargas - it sounds 'stunning'. This from Wikipedia:
I hadn't thought of a road-trip type murder story before but goodness, for an armchair traveller like myself, it works a treat! Especially one who loves mountains as I do.
Adamsberg himself does not join the team until halfway through, but does appear before that concerned with other things. He's following the news of the murders on TV though, but has no idea why apart from the fact that he's from a mountainous region himself (The Pyrennes) and knows how isolated and different the people there can be with their unusual superstitions. The book is chock full of these quirky characters and that makes it very real and very amusing.
As to the mystery itself, I had an inkling early on but abandoned it pretty quickly, which I shouldn't have done. But the joy of this story is not actually in the eventual outcome but in the getting there... 'the journey' as they say. Loved it and am now looking for the next instalment.