When a new director takes over a series, there are bound to be changes. This happens in the Harry Potter films, as Alfonso Cuarón directed Harry Potter and the Prisoner of Azkaban after Chris Columbus directed the first two films in the series. Many fans consider this to be the best book in the series, which created high expectations for the film adaptation.

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Cuarón brings some stylistic changes to the franchise, but there are also some changes in content that differ from the book. Some characters and storylines from the books are cut while others are condensed. Check out these 10 differences between the book and film Harry Potter and the Prisoner of Azkaban.

Where Floating Aunt Marge Ends Up

Aunt Marge flies away in Prisoner of Azkaban

Aunt Marge gets blown up in the book after verbally abusing Harry, but she only ends up floating to the ceiling of Number 4 Privet Drive. The situation is more terrifying for her in the film, as she floats out of the house and into the sky despite Vernon Dursley's best efforts to pull her back onto the ground.

It is later mentioned in the movie that the floating Aunt Marge is seen circling a chimney in Sheffield.

Harry Asks Cornelius Fudge For A Favor

Harry is desperate to get his Hogsmeade permission slip signed. In the book, he even asks Minister of Magic Cornelius Fudge to sign it so Harry can visit Hogsmeade with all of his friends.

Fudge does not sign the permission slip. While Fudge does check on Harry at the Leaky Cauldron, Harry does not ask him to sign the permission slip in the film.

Flying On Buckbeak

Harry Potter and Buckbeak flying.

Harry's Buckbeak flight is much more extravagant in the film. Buckbeak flies all around the Hogwarts castle and across the Great Lake. Harry even lets go of Buckbeak for a moment and laughs with triumph, joy, and a sense of freedom.

In the book, Buckbeak just flies once around a paddock in the Forbidden Forest. It is also made clear that Harry much prefers flying on a broomstick than flying on a Hippogriff.

No Cho Chang

The movies don't introduce Cho Chang until Harry Potter and the Goblet of Fire. The Prisoner of Azkaban is the first book to introduce her, though. She is Ravenclaw's Seeker and faces Harry in a Quidditch match. During the game, she tails Harry in order to find and catch the Golden Snitch.

Despite this strategy, Harry is able to catch the Snitch first and secure a Gryffindor victory over Ravenclaw. No Gryffindor-Ravenclaw Quidditch matches are shown in the film, which takes away an opportunity to introduce Cho before the next film.

Harry's Patronus Memory

Harry Potter and the Prisoner of Azkaban Patronus Daniel Radcliffe

In order to cast a Patronus, the spellcaster needs to think of and concentrate on a happy memory. The happier the memory, the more effective the Patronus will likely be. When Lupin first teaches Harry to cast a Patronus, it takes Harry a few tries before he is successful. The happy memory that ends up working for him is the memory of finding out he was a wizard and knowing he would finally be free of the Dursleys.

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The first happy memory that Harry uses to cast a successful Patronus in the movie is a made-up memory of his parents talking. In the film, he is able to cast a successful Patronus on his second attempt, but in the book, it isn't until his third attempt that he is successful.

When Harry Gets The Firebolt

Harry and his classmates with the Firebolt

Harry's prized Nimbus 2000 broomstick is destroyed in the Quidditch match against Hufflepuff. His godfather Sirius Black sends him a Firebolt to replace his destroyed broomstick. Harry receives the Firebolt about halfway through the book and doesn't know who sent it.

Harry doesn't receive the Firebolt until the end of the film, though. Even though there is no note, the Firebolt also comes with one of Buckbeak's feathers, making it clear that the gift is from Sirius as he escaped with Buckbeak.

Harry & Gryffindor Winning The Quidditch Cup

Harry plays an integral role in helping the Gryffindor team secure some impressive victories during his first two years at Hogwarts. Extenuating circumstances prevented Gryffindor from winning the Quidditch Cup during his first two years, though.

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That comes to an end in the book, as Harry and the Gryffindor team finally win the Quidditch Cup. This sweet victory isn't shown in the film. The only Quidditch match to make it into the movie is the first one against Hufflepuff when Harry's broomstick is destroyed.

The Hogwarts Choir

harry potter choir

The Prisoner of Azkaban film introduces viewers to a Hogwarts choir that doesn't exist in the book. Professor Filius Flitwick directs the choir as they sing the memorable "Double Trouble" song, complete with croaking frogs.

After they finish singing, the choir is met with applause and Albus Dumbledore delivers his welcome speech for another year at Hogwarts.

Pigwidgeon & The Letter From Sirius

Ron's owl Pigwidgeon is seen in the later films, but viewers are never shown how Ron got him in the first place. Ron receives the owl from Sirius Black. Sirius knows that Ron needs a new pet now that Scabbers has been revealed to be Peter Pettigrew.

Pigwidgeon also comes with a letter to Harry where he signs Harry's permission slip to go into Hogsmeade. Without the letter, it is unclear in the future films how Harry is allowed to enter Hogsmeade, as he is never shown to have gotten his permission slip signed.

Missing Backstory For The Marauders

Sirius Black in the Shrieking Shack Harry Potter and the Prisoner of Azkaban.

The film omits a lot of backstory concerning the Marauders. It isn't explained that the Shrieking Shack and Whomping Willow were first used so Lupin had a safe place to go when he transformed into a werewolf during the night of the full moon.

There also isn't an explanation of how James, Sirius, and Peter learned to be Animagi so they could safely be with and support Lupin when he transformed into a werewolf. Additionally, the film doesn't fully delve into Snape's hatred of the Marauders and how this connects to their use of the Shrieking Shack.

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