The story takes place in Shanghai in 1934. Lu Yan, the former chief detective, lived in the concession after his mentor was killed and opened a detective agency. A bizarre beheading of a dancer involved him in a huge whirlpool of conspiracy. As the investigation deepened, Lu Yan discovered that the murder case was implicated in the infiltration plan of the Japanese intelligence organization "Xuanyang Society" - the "Jackdaw Project". On the way to pursue the truth, he got acquainted with upright reporters, forbearing doctors, and low-level newsboys, and also dealt with forces such as police house ghosts and Japanese compradors. The novel combines hard-core reasoning and social narrative. In the suspense of secret room puzzles and code cracking, it depicts the struggle, betrayal and persistence of small people in turbulent times, and shows the everlasting glimmer of light in the darkness.
