In 1927, the isolated city in the south of the Yangtze River was gradually involved in the competition between domestic and foreign forces with the great changes of the times. As a private detective, Shen Ruiyao, because of the unsolved family tragedy many years ago, teamed up with female newspaper reporter Rong Manzhen, and discovered bizarre cases one after another in the seemingly peaceful streets, involving multiple interest groups such as politics, business, underworld, and underground parties. As the investigation deepens, each of the protagonists has to face the torn apart of their own families, revolutionary ideals, emotional entanglements, and personal beliefs, and eventually gradually uncover a series of serial mysteries—including the biggest mystery in their own hearts. The book has a rigorous volume structure. Each volume independently investigates the case, advances the main line as a whole, and finally achieves the climax and revelation of the truth.