Gu Xihe, a young man from modern times, accidentally traveled to Bianliang in the Northern Song Dynasty and was involved in a series of mysteries in Kaifeng Mansion. Relying on the skills given by the mysterious system, he gradually uncovered the huge conspiracy hidden under the market, starting from the strange smile on the face of Su Waner, the embroiderer who died mysteriously. In the process, he met Yun Shuwei, a forensic medicine student who also traveled through time. The two collided with modern criminal investigation knowledge and ancient laws, and cracked the eccentric robbery case that specializes in stealing women's white socks, and the old shadow knife gate case with wide implications. They also discovered that the smile on the face of each deceased person hides a revenge code that spans ten years.
The appearance of Nan Xia Zhan Zhao provided them with military support, while the appearance of the Five Rats made the situation more complicated - the tracking technique of Lu Fang, the Sky-Drilling Rat, the mechanism technique of Han Zhang, the Earth-Through Rat, the formation-breaking technique of Xu Qing, the Mountain-walking Rat, and Jiang, the River-Changing Rat. Ping's water combat skills and Chinchilla Bai Yutang's wisdom, sometimes cooperating with the Kaifeng Mansion, and sometimes clashing due to their positions, became the key force to advance the case in the process of cracking the corruption case of Li Song and his son and finding the secrets of the Shadow Sword Sect.
When modern forensic knowledge meets ancient grievances, and when system skills compete with the Five Rats' stunts, Gu Xihe and Yun Shuwei not only have to face the pursuit of murderers such as Li Zhong, but also have to find their way home in the dislocation of time and space. This is a detective adventure that spans a thousand years, and is also an epic battle between justice and conspiracy. Under the red walls of Kaifeng Mansion, everyone is fighting for the truth and belief.
