When does Wings of Fire return?

Wings of Fire is a series of epic dragon fantasy novels written by author Tui T. Sutherland. Over 14 million copies of the books have been sold, and it has been on the New York Times bestseller list for more than 214 weeks. The series currently consists of three arcs of five books apiece, which focus on young dragons ("dragonets") fulfilling/subverting prophecies to save their world. Fifteen books in the main series have been released, as well as four novellas, two extended-length standalone novels and two companion books.