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The 21 Best-selling Books of All Time


18
Harry Potter and the Prisoner of Azkaban – 55 million
Author J.K. Rowling arrives for the U.K. premiere of the film version of her novel "Harry Potter and the Prisoner of Azkaban."
Author J.K. Rowling arrives for the U.K. premiere of the film version of her novel "Harry Potter and the Prisoner of Azkaban."
Alan Davidson/Getty Images

In this third installment, released in 1999, Harry and his friends have adventures involving werewolves and time travel at Hogwarts and learn a bit about Harry's parents, James and Lily, who died protecting him.