From the liner notes

A dazzling mix of shocking family drama, picturesque seaside landscapes and three generations of brilliant French actresses—the luminous Chiara Mastroianni, sexy ingénue Laura Smet, and grand dame Danielle Darrieux—Towards Zero (L'Heure zero) is a smart, smoldering and thrilling update of one of Agatha Christie's most enduring works.

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