In the summer of 2017, at a high school in a small southern city, Wen Xiran, stifled by her family, and Chen Nanzhou, alone and with no one to rely on, meet by chance when he comes to her rescue in class. She is trapped by the ties of family, while he shoulders the burdens of life. These two lonely souls comfort each other through notes in their exercise books, the sweet scent of orange candies, and late-night explanations of homework problems. Together, they quietly promise to go to Nanjing and admire the plane trees.
But on the eve of the college entrance exams, a storm of reality suddenly hits. Wen Xiran's mother's fierce opposition and the news that Chen Nanzhou's father has been seriously injured at a construction site shatter their hopes. He rushes to Shenzhen to work through the night and raise money for medical bills, leaving behind an unfulfilled promise and a yellowed train ticket. She enters the exam hall alone and gets into a university in Nanjing with a broken heart, but has no one to share her joy with.
Three years later, in late autumn, fate reunites them in the cruelest way. Wen Xiran is diagnosed with cancer and spends her days in a hospital bed. Chen Nanzhou has struggled at the bottom of society, his original hopes unchanged but with no power to turn things around. As they struggle with their feelings after reuniting, old keepsakes bring back their sweet memories, but reality still yawns between them. Medical bills, her illness, and the truth that came too late deepen the sorrow of loving someone they cannot be with.
In the end, Wen Xiran dies as plane tree leaves fall in late autumn, leaving behind a note that reads, "If we meet again, let it be in spring," and half an orange candy. With the silver bracelet he has repaired, Chen Nanzhou returns to their small city every late autumn to mourn the young love that reality crushed beneath a plane tree. This belated "Letter from Late Autumn" is filled with missed chances, regret, and unforgettable longing. The story of these two young people remains forever frozen in the wind between Nanjing's plane trees and their small southern city.
Theme: Love and regret in the face of an unpredictable fate. By contrasting the purity of young love with the cruelty of reality, this story explores how forces beyond our control crush individual lives, and gives voice to the enduring longing that remains behind regret.