Matthew Quirk’s “The Directive,” a sequel to his bestselling novel “The 500,” imagines a heist to steal billions from a trading desk at the Federal Reserve. Jeffrey Brown talks to Quirk about how he researched the high-stakes break-in.

Young adult fiction is one of the most successful categories of book sales for the publishing industry today, and authors who've traditionally wrote for an older crowd have begun to dip their pen in YA ink.