During spring break at an all-inclusive resort in Puerto Vallarta, Hannah, the narrator, covertly watches Jackson Cole—her best friend Emelia “Emmy” Cole’s older brother—from a poolside smoothie stand. She has carried an unrequited crush on him for 10 years, and a humiliating incident during the previous winter break continues to weigh on her. As Hannah prepares to leave for college and Emmy plans to travel the world, she’s also struggling with the prospect of their impending separation.

Hannah brings Emmy a smoothie on the beach. Emmy is cheerful and effusive but notices Hannah’s subdued mood and presses her. Hannah deflects. When Emmy mentions that Jackson will eventually regret missing his chance, Hannah keeps quiet—Jackson already knows about the crush, and it changed nothing. Emmy proposes a vacation fling to reset Hannah’s feelings, but Hannah refuses. Emmy is currently on her third vacation boyfriend of the trip, cycling through boys at her usual pace.

In the ocean, Hannah is startled by a paddleboarder, who introduces himself as Ben. They flirt briefly after a wave knocks Hannah underwater and Ben helps her regain her footing. Emmy swims over, and Ben’s attention immediately transfers; he introduces himself as Bennett Mulholland and offers to teach her paddleboarding.