The fourth film of firefighter-turned-director Yang Shupeng, Blood of Youth follows a young hacker named Su Ang (Oho Ou), who anonymously tips off the police about the remains of a woman buried in the woods near the city of Hangzhou. Detective Zhang (Zhang Yi) discovers the victim was beaten to death almost two decades ago, and starts investigating the events that lead to her death.

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.