Towards Zero (2007)

When Guillaume has the bizarre idea of inviting his ex-wife Aude to a family reunion at the luxurious coastal estate of his wealthy Aunt Camilla, his tempestuous new wife Caroline becomes filled with rage. Guillaume hopes that they'll become friends but the two women despise one another. But things turn ugly when Camilla is found dead in her bedroom - and only the trusty Inspector Bataille can put together the pieces. But as the Inspector untangles her mysterious death, he also begins to unearth dark family secrets, brewing jealousies, and perhaps even a murderer in their midst.