Shōzō Saitō, an elderly farmer in Hirosaki, Aomori Prefecture, shares a modest life with his wife Ine. Married over fifty years, he occasionally regrets their inability to afford luxuries. A transformative moment occurs when he and Ine discover a golden apple on a tree planted during their wedding, consuming it together. Overnight, Shōzō physically reverts to his 20s while retaining his gray hair, later understood as a manifestation of an hourglass symbolizing their shared lifespan. This grants him voluntary control over switching between youthful and elderly appearances, preserving some youthful vigor even in his aged form. Born a second son into a farming family, Shōzō endured a harsh youth under his demanding and abusive father, who imposed strict household rules and forbade marrying Ine. This sparked physical confrontations and estrangement. Bound by an arranged marriage, Shōzō defied tradition to wed Ine for love—a progressive act for their era. His lack of formal education fostered persistent insecurity about his worth as a husband, heightened by Ine’s privileged background. Despite these doubts, Shōzō exhibits unwavering devotion. Learning Ine might die within a week, he sacrifices half his remaining lifespan for her. His rejuvenation rekindles physical attraction, though he often withdraws privately rather than express it openly. Their bond remains central, characterized by mutual support and humor, like strategically using elderly forms for discounts. Shōzō actively fosters family connections, encouraging his granddaughter Mino’s romance with classmate Shōta by creating opportunities for them. He engages enthusiastically in community events such as sports festivals, leveraging his renewed energy. His practicality blends with quiet rebellion against past constraints, like sharing household chores equally to reject his father’s domineering legacy. In their final days, Shōzō and Ine pass away peacefully together in their sleep beneath the apple tree, content with their fulfilled lives and assured they did not outlive their family. Decades later, their legacy resurfaces when Mino and Shōta, now elderly, find another golden apple.