Every summer, Isabel "Belly" Conklin returns with her mother and brother to the beach house of her mother's best friend, Susannah, where she reunites with Susannah's two sons, Conrad and Jeremiah. For as long as she can remember, Belly has been the invisible younger sister, hopelessly crushing on the brooding and elusive Conrad, while treating the more easygoing Jeremiah as a close friend. But this summer, everything changes. Belly, played by Lola Tung, finds herself caught in the center of an intense love triangle as both brothers suddenly begin to see her in a new light. The series, based on the novels by Jenny Han, beautifully captures the bittersweet ache of first love and the painful process of growing up. As old dynamics shift and long-held secrets surface, the idyllic beach town becomes the backdrop for a story of heartbreak, jealousy, and self-discovery. With a sun-drenched, nostalgic atmosphere, the show explores the fleeting magic of a single summer that can reshape the rest of your life.