Tom Rachman talks about his new novel, The Rise and Fall of Great Powers, about a young woman who travels the world to make sense of her puzzling past. Taken from home as a girl, Tooly Zylberberg found herself spirited away by a group of seductive outsiders, implicated in capers from Asia to Europe to the United States. But who were her abductors? Why did they take her? What did they really want?