Pig Cillian Murphy and Runt Elaine Cassidy grow up inseparable, born moments apart in the same hospital and living next door to each other, crafting a private, almost insular world that outsiders rarely enter. Their bond is intense and unrelenting, a mix of tenderness and hostility that they nurture with few rules and fewer strangers. They drift through school and family life with a shared sense of belonging that excludes everyone else, and their relationship remains largely platonic yet charged with a lurking volatility as they edge toward adulthood. The film presents this closeness with a cool, observational eye, never glamorizing it but also never softening it, letting the intimacy and danger coexist in equal measure.
As the countdown to their seventeenth birthday begins, Runt is drawn into a new current: Marky [Darren Healy], a fellow student who becomes part of their already fragile orbit, while Pig’s feelings for Runt sharpen into something more urgent and consuming. The dynamics between the three of them become a delicate, dangerous dance, where affection, fear, and jealousy jostle for dominance. The tension between Pig’s longing and Runt’s uncertain responses slowly reshapes their relationship, moving it beyond the realm of pure companionship into a terrain that feels increasingly unstable.
Pig’s volatility escalates, and after a nocturnal rampage at a nightclub, he kisses Runt, an act that unsettles them both and signals a future that neither fully knows how to handle. Runt, caught between loyalty and a growing need to protect herself, struggles to reconcile the comfort of their shared world with the reality of his mounting intensity. Their bond is tested not only by their own feelings but also by the concerns of others—teachers, friends, and most of all, Mrs Monroe [Marie Mullen], Pig’s mother—who worry that the climate around them is spiraling out of control.
With the help of her parents and Pig’s mother, Runt is sent away to a boarding school, a decision that shatters the life they have built together and leaves Pig devastated. The separation forces both teens to confront who they are apart from the other: Runt begins to adjust to the new routine and even makes a friend, while Pig wrestles with loneliness and a sense of loss that grows heavier by the day. The move sets in motion a dangerous longing to reclaim what was lost, a longing that drives Pig to pursue a risky reunion.
On their seventeenth birthday, Pig makes the perilous journey to the boarding school and pleads with Runt to run away with him. She agrees, and the two slip back into the world where they once felt most at home. Their path leads them to The Palace, a nightclub that becomes the scene of a crucial, catastrophic turn in their lives. It’s here that Runt reconnects with Marky on the dance floor, and Pig’s jealousy erupts into a fatal rage. He beats Marky to death, a moment that collapses the fragile safety of their shared orbit and forces them to flee.
The couple escapes to the beach, a familiar, intimate landscape where they have spent countless hours. They spend a heady, reckless night together, a last, charged communion before the inevitable consequences catch up with them. In the morning, Pig wordlessly allows Runt to smother him, choosing the punishment that awaits him rather than facing a life without her. As the first light stretches over the ocean, Runt gazes out at the endless horizon and wonders what the future holds for her, now that the world they built together has collapsed around them.
