Recently divorced, Marion decides to spend the end of summer in the family beach house on the Normandy coast. She takes her young cousin Pauline, who is delighted to prolong her holidays, along with her.
At the beach, they meet up with Pierre, Marion's ex-lover. He offers to teach them windsurfing and introduces them to Henri, who invites them to his place. While at the local casino, Pierre confesses his love to Marion, but she is now attracted to Henri. Pauline, meanwhile, has met Sylvain...