Private detective Luo Datie returns to his alma mater and remembers an incident from more than twenty years ago, back in high school, that changed many people’s lives. He fell in love with Qu Qianqian, the prettiest girl in his grade, but their teacher, Gao Shizhan, forcibly broke them up. In a fit of rage, Luo Datie hit the teacher and was expelled. After leaving Luo Datie, Qu Qianqian got together with Shangguan Chu, the top student in their class. Shangguan Chu got into Tsinghua University as he had hoped, then went to the United States with Qu Qianqian. No one expected that after earning a professorship there, he would return to China with his wife and take a position at Jiangcheng University in the provincial capital, his hometown. His return inadvertently stirred up the thoughts of several people.
Gao Yu, who is studying at Tsinghua, is the only pillar in Gao Shizhan’s life. He wants to pursue a graduate degree under Shangguan Chu, leaving Gao Shizhan deeply anxious. In a rush, Gao Shizhan goes to Luo Datie for help. When Shangguan Chu is involved in a car accident, it exposes the trap the teacher set twenty years ago. Back then, Gao Shizhan chose Shangguan Chu, a student with both an excellent physique and a brilliant mind, to fulfill his own special purpose. But when his scheme strayed from its intended course, he did not hesitate to drag the innocent Qu Qianqian and Liu Xiaoge into it, affecting the fates of Luo Datie and Ma Duo as well, and was even willing to risk his life. Can a teacher make mistakes? Teachers are human, and humans make mistakes. A teacher’s mistakes hurt students and shape their fates.
