It's near the end of summer. Both Parisiennes, married Marion, who is close to divorcing her husband of a few years, has agreed to act as the guardian for her fifteen year old cousin Pauline in staying at the family house a few miles away from the Normandy coast, they planning to spend most of their days at what should be the relatively quiet beach due to it being the end of the season. Pauline has already spent two months of her summer on vacation with her parents and thus is looking for a little liberation. Their first day at the beach, Marion and Pauline run into Pierre, one of Marion's old still single boyfriends who is teaching windsurfing, and one of Pierre's slightly older students, divorced Henri, the four who end up spending much of their time together, especially after Henri's adolescent daughter, Marie, heads home to her mother. One of their first conversations turns to the topic of love and sex, and what they see for themselves for their own circumstance. This discussion ends up being prophetic in how their interactions turn out. Pierre, who wants to fall madly in love, believes that it can only develop slowly, and has fallen in love with Marion all over again in seeing her after their five years apart. Marion, who also wants to fall madly in love, tends to be attracted to the unknown. As such, she finds Pierre too known a quantity, with Henri that man of mystery with who she is falling in love. Henri wants sex without commitment, he who will take the sex from whoever he is attracted regardless of their situation. And Pauline, who has never had a serious boyfriend, befriends similarly aged Sylvain, for who she does develop feelings. What happens between Pauline and Sylvain is not only affected by what Pauline gleans from that first night conversation, but also how the three adults deal with sex and love with each other.