"Alien" is a fascinating novel by the Norwegian writer Jon Fossum, which tells the story of a criminal detective investigation into a mysterious murder. The main character, inspector Konrad Sirtak, uses all his knowledge and skills to solve a mysterious crime. In this book, readers will not only enjoy the intricate plot and unpredictable twists, but also delve into the complex psychological portraits of the characters, analyzing their motives and secrets. "Alien" is not only a thriller, but also a study of human souls, in which every detail matters, and every character hides his dark side.