In the 2010s, the southern city of Yunxi is crossed by a river and holds the memory of a youthful romance, tender yet tinged with regret. Lin Zhixu returns carrying the regrets of her past life: the letter she never sent, the “I love you” she never said, and the silent figure of Shen Tingbai, all things she refuses to let happen again. This time, she resolves to take the initiative and get closer to Shen Tingbai. But Shen Tingbai, whose hearing is impaired and who has worn hearing aids for years, is used to building walls of distance and always retreats when she approaches. An encounter at Shiguang, the secondhand bookstore behind the school, an awkward hand-holding and confession by the river, the help of her loyal childhood friend Song Yuan, her lively friend Zhou Muye, and the quiet support of both their mothers all help the two teenagers slowly break down their barriers as they move closer and pull away, trying to rewrite the missed connection of their past life.
