The little-known detective Sun Dasheng (played by Wang Qianyuan) was born and died on the front line of the investigation of the case. On an ordinary day, he suddenly heard that Zhao Yongqiang, a car mechanic with whom he had a relationship, committed suicide by jumping off the building. Zhao Yongqiang had previously rented a demolished house, but the demolished house was forcibly demolished overnight. Not only were he and his son driven out, but even the prepaid rent was wasted. After that, Zhao took his son to find Zhao Tai (played by Bao Beier), the general manager of the real estate developer Taihua Group, but was beaten and humiliated. After that, Sun Dasheng tried to investigate the matter, but was obstructed by Taihua Group and even the police, and Zhao Tai's attempt to bribe him angered the upright and stubborn Sun Dasheng. In order to settle the matter, the domineering Zhao Tai did not hesitate to use all kinds of dirty means, and the battle between good and evil officially kicked off...