American college student Molly, Eireann Harper, travels to Mexico to study Spanish and pursue photography. She hopes to explore ancient ruins and capture the landscape in between lessons, using any free moment to focus on her camera, but she soon finds herself dragged along with fellow students who care more about partying than the curriculum.
Meanwhile, Diego, Diego Cataño, a teenage Mexican boy, secretly falls in love with his cousin Jero García. The crush leads him to moments of awkward bravado, even as he injures a toenail one day during a soccer game while trying to impress her.
Molly returns to Mexico during a break to photograph the ruins she missed, and she ends up renting a room from Diego's mother, Mariana Elizondo. Mariana is renting it out to raise money for an operation for Diego's grandfather, Salvador Elizondo. Through this arrangement, Molly and Diego begin to spend time in closer proximity, and a quiet bond starts to form between them.
As the days pass, the two spend moments together—often at the beach near Diego's grandmother's ranch—where Diego's feelings deepen, but he keeps them guarded and unspoken. The contrast between Molly's evolving perspective and Diego's burgeoning crush creates a growing tension, with the world around them continuing to move at its own pace.
When Molly eventually leaves, Diego secretly buys a plane ticket to New York City to visit her, deceiving his parents by claiming he is going camping with friends for the weekend. Once in New York, he calls Molly and tells her he has arrived to accompany his father on a business trip, and she takes him to Coney Island, where they spend a day together and navigate the gap between their different lives.
Before returning home, Diego reveals that he was not there with his father and that his visit was a sincere, if ill-judged, attempt to see her. Molly responds with warmth, calling him sweet but noting the age difference, and she changes her phone number so that he cannot easily reach her, permitting both of them to move on in their separate directions.
Months later, Molly returns to Mexico for a third time, still having never seen the ruins she sought, and travels there alone without bringing her camera. She debates reaching out to Diego but ultimately decides against it, sensing that he has likely moved on with his life. The film closes with Diego chatting casually with Jero García about girls, already pursuing a new romance and offering no mention of Molly.
