Top lawyer Su Wan takes on a serial murder case. After each murder, the killer leaves one of her business cards at the scene. Detective Lu Chen is assigned to investigate and suspects Su Wan has some connection to the killer. Forced to work together, they discover that the killer’s methods closely match those of Lu Chen’s “shadow personality,” missing for years. As the truth gradually comes to light, Su Wan realizes she is not just the defense lawyer in the case, but also the “judge” the killer has carefully chosen. Every business card is a declaration of war against Lu Chen, and the game’s end lies in the dark past they all share.