Harry Potter and the Prisoner of Azkaban attacked by a big black dog, which Harry has seen several times before. The dog drags Ron through a tunnel under the Whomping Willow into the Shrieking Shack. Harry and Hermione follow, and there is a brief standoff when they find Ron with Sirius Black, who has transformed from the dog. Lupin enters, and they explain the situation to Harry and his friends: Lupin is a werewolf, which led to his friends James Potter, Sirius Black, and Peter Pettigrew becoming animagi. Lupin explains that Scabbers is Pettigrew in his animal form; he has been hiding from Black, whom he had
Harry Potter world began holding events to coincide with the midnight release of the books, beginning with the 2000 publication of "Harry Potter and the Goblet of Fire". The events, commonly featuring mock sorting, games, face painting, and other live entertainment have achieved popularity with Potter fans and have been highly successful in attracting fans and selling books with nearly nine million of the 10.8 million initial print copies of "Harry Potter and the Half-Blood Prince" sold in the first 24 hours. The final book in the series, "Harry Potter and the Deathly Hallows" became the fastest selling book in history, moving