In winter, Atsushi, a yakuza, travels to a depopulated port town to find his missing sworn brother, Koga. He arrives at the ruins of a seaside mansion, only to unexpectedly encounter Anna, a woman he once cared for who, like Koga, has fallen into severe drug addiction. Bound to this abandoned estate and a silent, doomed harbor, the three begin to lose themselves in time—playing together as if they have regressed to childhood.