Su He, a seventeen-year-old leukemia patient, met Lin Zhao, a boy of the same age, in the sterile warehouse of the hospital. The two were in critical condition and happened to be matched with the same bone marrow donor, but the amount of bone marrow was only enough for one person to transplant. Lin Zhao voluntarily gave up the opportunity and gave the "optimal match" to Su He. Su He successfully transplanted and recovered well; Lin Zhao was forced to use a higher-risk haploidentical transplant (from his father), but suffered severe rejection after surgery and his life was hanging on by a thread. During the recovery period, the two maintained their relationship by passing notes, sharing headphones, and writing a "future diary" together. On New Year's Eve, without telling the doctor, the two secretly climbed to the "Universal Tower", the tallest building in the city, hugged each other tightly and kissed for the first time amid the hustle and bustle of tens of thousands of people counting down. After a short period of sweetness, Lin Zhao died of infection caused by chronic lung damage. Su He was devastated, but when sorting out his belongings, she discovered that he had written a ten-year birthday letter to himself and left a diary filled with "Our Future". A year later, Su He's condition relapsed. Before her death, she donated their story to the Blood Disease Foundation. Many years later, a commemorative plaque was erected on the top of the Universal Tower: "Su He & Lin Zhao. 2023.12.31. They were here and loved."
