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
The Magical Worlds of Harry Potter approval from Rowling, and has since received positive reviews from critics. An updated version of "The Magical Worlds of Harry Potter" was published in 2004 by Berkley Books. "The Magical Worlds of Harry Potter" explores the references to history, legends, and literature in J.K. Rowling's "Harry Potter" novels. David Colbert, the author of the book, told the "St. Louis Post-Dispatch" that the "Harry Potter" novels "are [...] literary treasure hunts for [Rowling's] readers. What seem like funny-sounding names and places and excursions into fantasy all have a basis in either history, myth or legend." He added, however, that he thinks