Christopher Briney, and Gavin Casalegno returning, the story reportedly dives into heartbreak, loyalty, and the moment Belly must finally choose her future.

The third and final season of Jenny Han’s heartfelt adaptation has delivered its emotional climax on Prime Video. Premiering with a two-episode drop on July 16, 2025, the 11-episode run unfolded weekly on Wednesdays at 3 a.m. ET / 12 a.m. PT, culminating in the supersized series finale on September 17, 2025. Now fully streamed as of March 2026, Season 3 stands as the definitive conclusion to the beloved trilogy-inspired series, giving fans the long-awaited resolution amid waves of heartbreak, unwavering loyalty, and transformative choices.

Set four years after Season 2’s beachside revelations, the season finds Belly Conklin (Lola Tung) in college, engaged to Jeremiah Fisher (Gavin Casalegno) and planning a future together. What starts as wedding preparations in the familiar glow of Cousins Beach spirals into chaos when Conrad Fisher (Christopher Briney) reenters the picture, confessing lingering love and forcing buried feelings to surface. The love triangle—once a youthful summer fling—matures into a profound test of loyalty, self-discovery, and what it means to choose freely.

The Fisher brothers refuse to fade into the background. Conrad’s quiet persistence and emotional vulnerability clash with Jeremiah’s steadfast commitment, creating tension that strains their brotherhood to its limits. Heartbreak unfolds in raw confrontations, family secrets, and the weight of Susannah’s enduring legacy. Belly, caught between the intensity of her first love and the comfort of her current partner, faces the ultimate crossroads: a decision that reshapes not just her path but the lives of everyone around her.

Heartbreak and Loyalty: The Brothers’ Unbreakable Bond Tested

Season 3 amplifies the stakes with mature themes. Belly and Jeremiah’s engagement crumbles under revelations—Conrad’s beachside confession, a mix-up of Susannah’s letters exposing lingering doubts, and the painful realization that old flames never fully extinguish. Jeremiah, ever the loyal golden retriever, fights to hold on, while Conrad grapples with regret and growth, ultimately earning his brother’s reluctant blessing to pursue what his heart never released.

The emotional fallout is devastating yet cathartic. Brotherly arguments erupt, loyalties fracture, and forgiveness becomes hard-won. Jeremiah finds his own path forward—closure with Belly and hints of new beginnings—while Conrad confronts his barriers, emerging more open and vulnerable. The brothers’ relationship, strained by years of rivalry, endures through pain, proving their bond unbreakable despite everything.

Belly’s journey centers on agency. After calling off the wedding and fleeing to Paris for independence, she explores life on her own terms—new friends, a brief romance with Benito (Fernando Cattori), and self-reflection far from Cousins. Her growth shines: no longer the impulsive teen, she’s a young woman choosing with intention.

The Moment Belly Chooses Her Future

The finale, “At Last,” brings everything to a head in Paris. Conrad surprises Belly on her birthday eve, leading to a day of reconnection—sightseeing, shared memories, a vial of Cousins sand as a gift, and undeniable chemistry. An intimate night follows, but doubts creep in: Belly questions if their love is destiny or obligation tied to Susannah’s wishes.

Conrad, heartbroken, departs for Brussels. But Belly chases him to the train, wearing the infinity necklace—a symbol of their enduring connection. In a declaration set to Taylor Swift’s “Out of the Woods,” she affirms: “Conrad, I choose you of my own free will. If there are infinite worlds, every one of me chooses you in every one of them.” Their passionate kiss seals the endgame, blending romance with self-assurance.

This choice honors Belly’s growth—she selects Conrad not from pressure but authentic desire, after choosing herself first in Paris. Jeremiah receives grace and closure, moving toward his own happiness. The season deviates from the books with expanded emotional layers, modern twists like Paris adventures, and emphasis on free will, making the resolution feel earned and empowering.

Fan reactions split passionately: Team Conrad revels in the soulmate payoff, Team Jeremiah appreciates the respect given to his arc, and many praise Tung’s nuanced portrayal of Belly’s messiness and strength. The finale’s callbacks—the necklace, the beach sand, the chase—deliver catharsis while leaving room for reflections on love’s complexities.

With Season 3 complete and a movie sequel in development (filming slated for 2026), the story of summers, heartbreak, and choices closes beautifully. Cousins Beach may fade into memory, but the lessons of loyalty, heartbreak, and choosing one’s future resonate forever.

Dearest viewers, whether you rooted for Conrad’s intensity, Jeremiah’s warmth, or Belly’s journey above all, this final season delivers the head-on collision fans awaited: a choice that honors growth, heals wounds, and proves some loves are worth the wait. Stream it on Prime Video—the summers end, but the emotions endure.