The Power of Young Adult Fiction The remarkable box office success of "The Hunger Games," based on the first of a trilogy of books that have sold 23 million copies, demonstrates the power of young adult fiction and its passionate fans. The number of young adult titles published last year was up nearly a third since 2008, to almost 10,000, according to Bowker Books In Print. The genre's appeal has spread beyond teenage readers. Why has young adult fiction become such a phenomenon - even with older adults?