In the wintry expanse of Hokkaido, two couples seek a pause from their routine lives. Shinichi Suruga and his wife Haruko Suruga, both in their thirties, along with a younger pair, Eiji Haga and Yoko, drift through their days with a sense of restlessness and a sudden urge to swap partners for reasons they treat as trivial.
Shinichi and Haruko close their coffee shop, choosing to wander the quiet back roads of Hokkaido on a motorcycle, aiming for a hotel in Sapporo as if a change of scenery might change their relationship. Along the way, the pair of couples pass one another, and the encounter feels casual, almost fated, but the meaning soon becomes more tangled than either expected.
A roadside moment by a riverbank shifts the night into a turning point. Shinichi forgets that Haruko brewed the coffee and drinks it himself, a small lapse that wounds her pride and sparks a heated argument. The quarrel pushes Shinichi away, and Haruko, burning with anger, heads back toward her home. In the aftermath, Shinichi’s sense of fault deepens, and he continues his journey alone, while Haruko retreats, riding the edge of quiet resentment at the life she feels slipping away.
By chance, Shinichi discovers Yoko collapsed on the road. He helps her to her feet, and she confesses that Eiji left her stranded. This encounter binds the two more tightly in the moment, even as the tension between the two couples remains unresolved. Meanwhile, Eiji, stumbling upon Haruko’s house, is drawn to her by a mix of loneliness and curiosity. He persuades her to meet him again, and they end up at a drive-in for dinner, a setting that feels almost cinematic in its irony.
The night grows increasingly awkward as all four find themselves in the same space: Shinichi and Yoko, together, share a fleeting, uneasy intimacy, while Haruko and Eiji stumble through a fragile, imperfect attraction of their own. The couples end up engaging in sexual acts with each other’s partners, a bold experiment that brings fleeting satisfaction to Shinichi and Yoko but leaves Haruko and Eiji frustrated by a lack of genuine chemistry.
The next day, the mood has soured into mutual hostility. The two pairs sprint along their separate paths, each woman and man nursing resentment toward the other for the choices they’ve made. A radio moment interrupts their anxiety with fresh tragedy: a report of a couple dying in an accident, triggering a frantic rush toward the hospital as they fear that the unlucky pair might be themselves.
In a surprising collision of fear and relief, Haruko and Eiji race toward the hospital, only to run into Shinichi and Yoko, who have also heard the news and share the same fear about what might have happened to their partners. Haruko’s relief that they are not the ones who died gives way to a renewed, fragile hope that perhaps the fragile balance of their relationships can be repaired.
As the dawn approaches, Shinichi makes a quiet decision to rekindle his relationship with Haruko and heads toward the hotel in Sapporo, seeking a clearer sense of commitment and possible reconciliation. He waits in his room, but when Yoko arrives, the tension returns with a sharp, unspoken intensity. Then new information breaks: Haruko and Eiji have died in an accident. Yoko’s smile—an uneasy mix of triumph and longing—seems to imply she believes she can take Shinichi’s life and love for herself forever. Yet Shinichi, overwhelmed and overwhelmed by the shock, leaves the hotel in a literal and emotional hurry, leaving Yoko behind to face a future that now feels uncertain and solitary.
