In 1987, an unnamed 15-year-old girl (later revealed to be Diana Scalzi) is invited by Dr. Levy, a university professor and friend of her mother, to work as an au pair in Cape Cod for the summer. She ardently wishes to go, but her parents debate whether she is too young for the job. Her sisters tease her about the parties she will have and the boys she might meet and give her a yellow bikini for Christmas.

When her parents finally relent and allow her to go, she packs her bikini and some familiar books and travels to the Cape, where she looks after Dr. Levy’s children in their magnificent house and on the beach. She meets other girls working similar jobs and a group of boys who have just finished school at the prestigious Emlen Academy. One of the boys, Poe, takes a particular liking to her, and the two develop a close relationship as the weeks pass. At the end of the summer, Poe and the other boys invite Diana to a final bonfire party. She is excited and hopes that he will finally kiss her or confess his feelings for her. Poe gives Diana a drink, and she thinks she will never be as happy as she is that night.