Zhong Zhicheng's work often requires him to shuttle between various cities. On the K930 train bound for Hecheng, he accidentally encountered a familiar scene. The embankment between the green rice ears on both sides, and the rolling hills behind. This was his memory from middle school. The girl who played with him in middle school made him fall back into beautiful memories. Unexpectedly, he met his middle school classmate Yu Xiuxiang by chance in Hecheng. Xiuxiang was going through something painful, and Zhicheng could only silently protect her from behind. Cui Zemin, who was also a middle school classmate, was always secretly competing with Zhicheng because he was jealous of Zhicheng's intelligence, but accidentally put Xiuxiang into trouble. From then on, Zhicheng protected Xiuxiang from harm and began a battle of wits with the police and Zemin.