One long blast of a train whistle, and from then on, home was somewhere he could only gaze toward from afar. Half a lifetime spent adrift: regrets, debts, and longing. Then, forty years later, an accident takes him back to a morning forty years in the past. Through tears of joy, he sees his younger self, and from that day on, the two become brothers. This time, he no longer chooses to leave. Drawing on forty years of life experience, he rewrites his fate, turning regret, longing, and debt into companionship. At last, in the narrow gaps between what might have been, he pieces together a family reunion that is forty years overdue.