Ni Hao, Zhihua plot
All that Zhihan Yuan leaves behind when she dies is a letter to her two children and an invitation to a school reunion. Zhihan's younger sister Zhihua goes to the reunion in her place with the intention of telling them that Zhihan has passed away. It's not because of the crowds. There, Zhihua does meet a former classmate of her sister, Chuan Yin, with whom she herself was in love at the time. When she starts to correspond with Chuan, painful memories of high school resurface for her and him.