Cold Detective (2022)

When Hong Kong is rocked by multiple gruesome murders, the police forms a task force to investigate. Jun, once a brilliant detective who suffered a mental breakdown, begins his own investigation. Eventually, the police learn that the murder victims are all suspects of cold cases being rubbed out by a figure known as The Sleuth. Now, Jun and a detective from the task force are on a race against time to beat the brutal killer at its own game.