In a department store in London, a little girl called Sophie visits Santa’s magical forest with her grandfather. As they emerge from the forest, Sophie’s grandfather reports her missing . . . but the little girl’s right there. Is she a ghost, a twin, an alien abductee—or is there some simpler explanation? Twenty-six-year-old amateur sleuth Emily Castles has fifteen minutes to figure out the puzzle before the police are called and Christmas is ruined.