Police attempt to stop Nationalist agents from destroying public buildings in Ruancheng after the Red Army occupies the city.
Based on Zhu Dao-Nan's memoir "In the Flood of the Great Revolution", the film reproduces the historical picture of the changing circumstances of China before and after the Great Revolution through the pursuit, struggle and differentiation of young intellectuals such as Jin Gong-Shou, Gu Da-Ming, and Yang Ru-Kuan in the revolutionary tide.
Set in early 1960s, the police prevents spies from destroying city infrastructures before the National Day.