A female corpse was found in the Han River. After investigation, the police learned that she was a young student named Ying Ai (played by Shen Minxi). There are three young people of the same age as Ying Ai who are most suspected of Ying Ai's death. The first is Zheng Xun (played by Cui Shengxian), who was born in a broken family. Although he was abused, he still has an optimistic and cheerful personality. By chance, Zheng Xun and Ying Ai met, and the day before Ying Ai's death, the two stayed together. The second is a re-examination student named Minshu (played by Shengli). Although he is not familiar with Ying Ai, the video of Ying Ai that he secretly filmed makes him a suspect. Finally, Ying Ai's friend Enying (played by Xu Yicai) has the most serious suspicion because she has a close relationship with Ying Ai. After the complicated clues, who is the real murderer? The three people are convinced of their innocence, and they decided to join hands to investigate the truth of the case.