The film mainly tells that Lin Hongying, a trainee police officer, has finally joined the serious crime team of the Public Security Bureau after a rigorous test. The choice between love and hate is put in front of Lin Hongying.

During China's Warring States period, a district prefect arrives at the palace of Qin Shi Huang, claiming to have killed the three assassins who had made an attempt on the king's life three years ago.