Yesterday Once More Lin Tianjiao (Guo Shutong) is the top girl in her school. During one of her tests, she resorted to copying from notes, and is spotted by Gao Xiang (Bai Jingting), who is considered a wayward student. When the note was discovered by the teacher, Gao Xiang chooses to claim responsibility for trying to cheat. Lin Tianjiao feels apologetic towards Gao Xiang, and begins their friendship. Meanwhile, Lin Tianjiao’s good friend, Lu Tiantian (Wang Herun) is courting Ou Xiaoyang (Ding Guansen). However, due to his poor academic standing, Lin Tianjiao ignores him completely. Classmate Huang Tao (Li Hongyi) is secretly in love with Lin Tianjiao, but is too shy to express it. As a result, he and his best buddy, Li Tao (Zhao Wenlong) are at loggerheads with Gao Xiang.