In the 15th year of the Republic of China (1927), Shanghai, where five oceans coexisted and Chinese and Western cultures blended, continued to experience strange cases. Che Youyun, the former inspector of the Central Patrol House in the Shanghai Concession, committed suicide out of fear of crime. As an airborne inspector, Gu Yuan formed a four-member team with Che Youyun's adopted daughter Che Suwei, deputy inspector Kang Yichen, and reporter Cao Qingluo to break the rumors of feudal superstition. From the perspective of social science and psychology, they worked together to solve a series of strange cases, witnessing the joys and sorrows, love and hate between people from different classes, and jointly upholding the justice and fairness of the concession, breaking the folk superstition of strange powers and chaos. The four-member team became loyal comrades who could trust their lives and backs. On the way to solving the case, when the four gradually approached the truth of the suicide of the previous inspector, a black hand also reached out to them. Relying on the trust between Ji Yong and his comrades, the four-member team persistently pursued the truth, was not afraid of power, and destroyed the corruption and darkness of the upper echelons of the patrol house, proving the innocence of the former inspector Che You.