A Polish detective named Tadek, frustrated by the lack of progress in his career, becomes intrigued by an unsolved murder case. The victim, a businessman, was discovered dead in a manner resembling events described in the novel of an enigmatic author named Kozlow. Convinced that the book holds the key to solving the crime, Tadek embarks on an obsessive quest to connect Kozlow to the murder. He delves into the dark and seedy underworld of sex clubs and illicit activities, trying to gather evidence that links the novelist to the crime. Despite mounting pressure from his superiors and a strained relationship with his wife, Tadek becomes more and more entangled in Kozlow's sinister world.

As Tadek digs deeper, he encounters a troubled woman named Kasia who has connections to both the murder victim and Kozlow. Kasia's harrowing experiences and insights provide Tadek with crucial leads, but also blur the lines between victim and perpetrator. Tadek's relentless pursuit of the truth ultimately takes a toll on his mental state, pushing him to confront his own demons. The detective's journey quickly evolves from seeking justice for an unsolved crime to navigating the murky waters of moral ambiguity and personal obsession.