The story takes place in Beijing in 1949. The combat hero Sun Guangda (played by Li Naiwen) left the battlefield and became a policeman. His partner is a man named Qian Yougen (played by Huang Zhizhong). Qian Yougen was already a policeman in the old society. He had the unique problems and bad habits of that era, which made Sun Guangda, who was upright, very uncomfortable. There were frequent conflicts and misunderstandings between the two. Qian Yougen's younger brother Qian Youcai died and was wrongly accused, which became a heartache for Qian Yougen and Sun Guangda. In order to clear Qian Youcai's grievances, Sun Guangda investigated the case and finally brought the culprit Zhang Youyi to the surface. In the end, Zhang Youyi was defeated by Sun Guangda, and Sun Guangda and Qian Yougen became lifelong friends.