Annette, 38, answers an ad from Paul, a farmer. She has only met him twice when she and her son Eric move in with him in the dead of winter. There Annette has to face Paul's hostile sister and her own past, which soon catches up with her.

In Paris, Ariane and Lena are sisters. Ariane writes photo novellas for the magazine "Toi et Moi." She's emotional and her long-time boyfriend, Farid, has her in a state because he won't propose, won't ask her to live with him, and often is unavailable. Lena is a cellist, quiet and circumspect in life and in her playing. She lives without passion with her boyfriend François; they're talking about having a baby.

Seaside takes place in a small coastal town on the Bay of Somme. The year-round inhabitants find ways to make their lives work; Paul, a lifeguard in the summer, works at the grocery all winter. His mother, Rose (Ogier) likes to play the slots just about anytime; his girlfriend Marie works in the local factory - the town's biggest business - but watching the summertime vacationers each year just makes her increasingly curious about what else might be out there. From these and several other stories, aided by close, revealing observations, we see a community perched between transition and stasis.