1935, Shanghai. Rainy nights, secret rooms, and unsolvable murders reveal a bloody mystery that has been sealed for twenty years.
Banker Du Shiming died in a locked study, leaving only an incomplete fragment of celadon at the scene. Cheng Mochuan, a criminal psychology detective who returned from studying in the UK, joined forces with the stubborn newspaper reporter Shen Qingyue to investigate, only to discover that the deceased was involved in a serial finger-breaking case 20 years ago - the victims of the "Shanghai Finger-Banging Demon" were actually closely related to Shen Qingyue's life experience.
As the investigation deepened, a mysterious organization called the "Celadon Society" surfaced. The disappearance of a dancer, the poisoning of a girls' school, the theft of a bank vault... Seemingly unrelated cases point to the same transnational cultural relics smuggling conspiracy. The unjust case of Cheng Mochuan's father and the mysterious death of Shen Qingyue's mother are also intertwined in this mystery.
When the truth approaches, they face not only the murderer, but also the darkness of the entire era.
