In a small town often covered with snow, there is a dim and lonely apartment where teenager Owen (Kodi Smit-McPhee) and his divorced mother (Cara Buono) live. This handsome little boy is sensitive and timid. He is often bullied by others at school, and his mother is a devout believer in religion and has no time to care for him. Owen can only hide in his small room, peek at the outside world through a telescope, or pretend to be a serial killer to release the depression and anger in his heart. One night, the beautiful and mysterious Abby (Chloë Grace Moretz) moved into the apartment and became Owen's neighbor. The two children who share a unique temperament are attracted to each other and gradually become good friends. At the same time, murders occurred one after another in the town, and Owen accidentally discovered the incredible secret of Abby... This film is adapted from John Ajvide Lindqvist's novel of the same name. The Swedish version was well received after it was released.