When a cooked corpse turns up in a sleepy town on the border of the Tang empire, the local magistrate employ the help of art forger Cheng Ren to decode the only clue left at the crime scene - a hellish painting holding an enormous secret.

On a day like any other, the residents of Hongnizheng - sleepy border town with a seedy underbelly, are shaken with the discovery of two bodies. Forensic pathologist Bai Qian Ji is immediately called to the scene of the brutal killings. The corpses belonged to a local artist Li Bai, who was found dead in a cauldron, having been broiled to a slow and agonizing death. The clues of the death seemed to lead towards the local distiller Hong Niang, who is eventually found appearing to have taken her own life. Clutched in her lifeless grip is a hellish painting named the Di Yu Tu, the painting points to clues of a deeper conspiracy. With mounting pressures from the central Tang government and a body count that continues to rise, the local magistrate is forced to employ the help of Cheng Ren, a two-bit art forger and lifelong friend of Bai Qian Ji's. Together they are tasked with profiling the perpetrator, a journey that leads them to a deep and sordid secret that involves many of the well-known residents of Hongnizheng.