Elena is a gorgeous fifteen-year-old forced to drag along pudgy twelve-year-old Anais as she trolls for boys in the cafes of a seaside resort where their family is vacationing. Treating Anais with casual cruelty, Elena smooches a handsome young Italian as her sister gorges on a banana split and later, in their shared bedroom, commands her to sleep as the twentysomething Fernando climbs in through the window. As Elena is deflowered, Anais writhes in fascination, envy and her own budding desire. When Elena's transgression is revealed to their parents, their furious mother breaks off the holiday and embarks on the long drive home with the girls in the back seat. The summer vacation is over but, as they discover on a tension-filled journey home, the family adventure is not.