Jiang Xiaobai has regained his memories, and Tong Li cannot bring herself to face him. Separately, they confront the truths left unsaid for 10 years—about the band September, to which Jiang Xiaobai and Mu Xiyu dedicated their youth; about the love triangle between Jiang Xiaobai, Mu Xiyu, and Tong Li; and about the painful circumstances that brought the trio together and ultimately led to the terrible tragedy that occurred on the day Tong Li left for America. At the end of it all, can Jiang Xiaobai and Tong Li accept the past and face the future together?
江小白醒后想起了过去的一切:校庆当天一起为佟离唱的歌,冤枉佟离将夕雨推下水,图书馆的畅谈,送给佟离的玻璃珠,未来得及对佟离说的喜欢。和小白一起追赶佟离的夕雨在途中遭遇了车祸,而夕雨的一切行为都只是为了让小白注意到佟离。走遍了所有和江小白留下记忆的地方并决定离开重庆的佟离,在机场被赶来的江小白挽留,无法放下夕雨和江小白在一起的佟离最终选择了离开。一年后,杂志社的各位都有了新的生活,小敏也如愿进入了文筝。而追赶不慎掉落玻璃珠的江小白也再次遇见了捡起玻璃珠刚刚归国的佟离。