A ferry leaves Saint Malo for England. Thomas, a French adolescent, meets Alice, an English woman in her thirties. The sea crossing encourages the woman to strike up a conversation, and then to enter into the game of seduction. Thomas lets himself be guided by her. He's tender, and sees her as someone alone and abandoned. In the evening he starts taking the initiative. At first she retreats, then she lowers her resistance and gives herself to him. As the ferry reaches Portsmouth, she promises to wait for him while he picks up his luggage. But when the boy looks for her, she's vanished. Finally he sees her stretching her arms towards a man and a child at the customs: Thomas, who's just made love for the first time, is left alone and depressed.