Harry Potter and the Prisoner of Azkaban (2004) is the third in the Harry Potter film series and was directed by Alfonso Cuarón. It stars the actors from the preceding films in the series, except for the role of Albus Dumbledore, which saw Michael Gambon taking over from the late Richard Harris. Much of the original crew also returned, including screenwriter Steve Kloves.

Tagline: Something Wicked This Way Comes.

Further information: Harry Potter and the Prisoner of Azkaban, and b:Muggles' Guide to Harry Potter/Books/Prisoner of Azkaban.

A mysterious convict, Sirius Black, escapes from Azkaban and sets his sights on Hogwarts, where dementors are stationed to protect Harry and his peers.

Some of the sets for the film were built in Glen Coe, Scotland, near to the Clachaig Inn. The indoor sets, including sets built for the previous two films, are mainly in Leavesden Film Studios. The Hogwarts lake was filmed from Loch Shiel in the Highlands of Scotland. Incidentally, the train bridge which was also featured in the Chamber of Secrets movie is opposite Loch Shiel and was used to film the sequences when the Dementor arrived on the train. A small section of the triple-decker bus scene, where it weaves in between many different cars, was filmed in Palmers Green in North London.

The backstory involving Moony, Wormtail, Padfoot and Prongs is not explained, though hinted throughout the movie. James Potter is actually not disclosed to have become an animagus.

No explanation is given as to why Snape hates both Sirius and Lupin so much.

The book explains that Sirius was supposed to be the Potter's "Secret Keeper" and thus he would have been the only one who could have told Voldemort their location. This is the reason why everyone so strongly assumed his guilt. At the last moment, however, he gave the task to Peter Pettigrew and only he and the Potters knew about it.

The explanation of how Sirius escaped from Azkaban and his knowledge of Pettigrew's location is not in the film, unlike the book where he tells that he saw a picture of Pettigrew (in rat form) in The Daily Prophet.

Oliver Wood and Cho Chang are not in the film.

In the book, the Hufflepuff seeker is explicitly identified as Cedric Diggory. In the film he is not identified by name and not played by the same actor as Cedric is in the next film.

The Quidditch House Cup is omitted. Only one Quidditch game is shown, thus the part in which Malfoy and his crew dress up as Dementors was also omitted.

All of Professor Trelawney's predictions except the ones about Harry's death and Voldemort's return are left out.

In the book, Hermione experienced a small mental breakdown due to the fullness of her schedule and complexities of time travel.

The film does not show how Hermione bought Crookshanks.

Sir Cadogan was cut from the movie, although he can be seen in deleted scenes on DVD.

The episode when Sirius sneaks into the Gryffindor dormitories was omitted, though events which happen afterwards are present in a deleted scene on the DVD.

Buckbeak had a series of trials and appeals that occurred throughout the year, only one is implied in the film. Also, there is no mention of Hermione helping Hagrid prepare.

Unlike in the previous films, Professor McGonogall's Transfiguration class is not shown, nor is Snape's Potions class. Instead, the film shows only those classes taught by new teachers: Divination with Professor Trelawney, Care of Magical Creatures with Hagrid, and Defense Against the Dark Arts with Professor Lupin.

At times, the dementors fly rather than glide.

In the movie, the presence of Dementors is shown to instantly frost over the surrounding environment; in the books, they were merely described as surrounded by a chill.

A shrunken head, voiced by Lenny Henry, is added to the Knight Bus.

Harry is caught with the Marauder's Map by Snape while wandering around at night trying to find Peter Pettigrew. In the book, it's after his second visit to Hogsmeade.

In the book, Harry was caught by Malfoy using the invisibility cloak.

Harry and Lupin get their first indication that Peter Pettigrew may be alive when Harry sees his name on the map, rather than in the Shrieking Shack scene.

"Moony" is spelled "Mooney" as an in-joke referring to Karl Mooney, one of the visual effects supervisors. In the DVD subtitles, it is spelled "Moony" as it was in the book.

Romantic tension between Ron and Hermione is more purposefully implied than in the book, despite many film critics falsely inferring the unintentional chemistry between actors Daniel Radcliffe and Emma Watson as a foreshadowing of a relationship between Harry and Hermione. J. K. Rowling approved of the implied Ron/Hermione relationship.

In Lupin's class, the boggarts are different from the book. For example, Ron confronts the boggart spider by giving it roller skates rather than removing its legs and Parvati Patil's boggart is a snake in the film, whereas it was a mummy in the book. In the book Lupin intercepts the boggart before Harry can face it. In the movie, Lupin's boggart took the picturesque form of an obvious full moon whereas in the book it was described as being a "silvery-white orb", or less obviously the moon.

Snape (who was going to bring Lupin his Wolfsbane Potion) discovered him heading for the Whomping Willow. He used Harry's Invisibility Cloak to follow Lupin in the book but wasn't wearing it in the film.

While in the Shrieking Shack, only Harry attacks and knocks out Snape, as opposed to Harry, Ron, and Hermione together. This had the bizarre effect of rendering the Expelliarmus charm very random—sometimes all it did was knock a wand out of someone's hand, but here it bowled Snape right over.

Ron's line in the book "If you want to kill Harry, you'll have to kill us too!" is given to Hermione.

In the film, when Lupin is teaching Harry how to perform the Patronus Charm, the happy memory that allows Harry to be successful is Harry "just talking" with his parents; in the book the memory is of Hagrid telling him he is leaving the Dursleys' to go to Hogwarts.

Originally Harry spent two weeks at London and bought all his books by himself except for Monster Book of Monsters which was his birthday present by Hagrid. In the film, Cornelius Fudge provides Harry with his books the night he runs away from the Dursleys.

In the book Mr. Weasley didn't tell Harry about Sirius. Harry had heard that accidentally.

In the book when Harry was caught with the Marauder's Map by Snape, Lupin was called using fireplace (floo powder network).

The Three Broomsticks scene where Harry learns that Sirius is his godfather is set differently. In the book, Harry, Ron, and Hermione are in the Three Broomsticks and overhear the conversation while hiding under a table. Eventually Ron and Hermione just looked at Harry, lost for words. The movie has Harry use his invisibility cloak to eavesdrop on the conversation, which is held in a private room of the Three Broomsticks.

In the movie, Harry threw snowballs at Malfoy while they were near Shrieking Shack, in the book this scene happened in spring, Hermione wasn't with them and Harry threw mud.

In the film, when Lupin transforms into a werewolf, Snape appears to instinctively shield Harry, Ron and Hermione, placing himself in danger.

The film shows an American-style werewolf (bipedal, extremely large) whereas in the books, Lupin becomes a normal (albeit vicious) wolf (werewolves and wolves being nearly identical).

In the book, when Sirius is captured at the end, he is locked in Professor Flitwick's office. The film has Sirius locked in a dungeon in a high tower.

At the end of the book, Ron receives, Pig, his owl from Sirius. He does not receive the owl at the end of the movie.

Harry receives his Firebolt at the end of his third year rather than at Christmas. It was originally sent to Harry anonymously by Sirius Black.

In the book, a letter sent by Sirius tells Harry that he sent the Firebolt. But in the film the Firebolt makes its only appearance at the end, and it is sent with one of Buckbeak's feathers giving Harry and friends a clue as to who sent it.

The third film departed from several conventions set in the first two movies, and had several stylistic changes. This is mostly due to the introduction of a new director to the series, but may also be explained by the fact that the third book of the series was significantly longer than the previous two books, and the director was given more freedom to adapt the book in the interest of screening time. Overall, this film is about ten minutes shorter than the previous films.

The Prisoner of Azkaban introduces a tone that is darker than the previous Harry Potter films. This change is attributed to both Alfonso Cuarón and the source material. There is also greater degree of physical darkness in the third film than in the first two.

All the Harry Potter books contain scenes relating to the mystery/adventure aspect of the stories along with emotional scenes designed to explore the characters. The first two films had a tendency to focus mainly on the mystery/adventure aspect, leaving out most of the emotional scenes, which inevitably bred criticisms of a lack of character development and related issues.

In the third film, the paradigm was reversed with more emphasis on Harry's angst than on the plot mechanics and literal faithfulness to the narrative. Some felt that this created a murky plotline (see "murky" plotting below,) but most film critics and many fans were more than pleased with these changes, believing it made the film stronger and the characters more interesting and believable than the two previous.

Some fans felt upset with minor continuity issues between the two previous, including the landscaping and layout of Hogwarts. Despite the fact the Harry Potter films are not considered canon, some fans found the lack of continuity irksome. These contradictions include:

In the first two films, Hagrid's hut is a short distance from the castle across a meadow, but in the third film it is much farther away and surrounded by hills.

In the first two films there are no mountains surrounding Hogwarts, but in Harry Potter and the Prisoner of Azkaban Hogwarts is featured in an enclosed mountainous valley, which is closer to the actual description in the books.

In the first two films, the Fat Lady's portrait was at the end of a long hallway, but in the third film it's moved to the room with the moving stairs.

Hagrid's hut is larger than in the first two films. However, this is consistent with the original description in the book.

In the second film, the Whomping Willow is right next to the castle, whereas in the third film it is now farther away from the castle, and is on a hilltop.

The hospital wing is moved to the top of a clock tower, with a view of the clock's face just beyond the doors. In the first two films, only a blank wall is visible beyond the doors.

The core Trio's wands have changed completely since the first film. Ron's has changed as he bought a new one after his old one was snapped. Harry's in now extremely rough, the handle looks thoroughly battered, as does the long rod part of the wand, and Hermione's wand has changed completely. In the first two films, it was a light handle with a dark narrow rod on the end of the handle. In this film, it is simply a long brown rod with an intricate vine-pattern surroundoing it.

Detractors say that, in contrast to the smooth and detailed rendition of the book, Harry Potter and the Prisoner of Azkaban features a hasty and fragmented succession of often unconnected events. Creating a plotline Roger Ebert described as "a little murky" in his largely positive print review. Entire patches of the original plot have been either left out or significantly altered. This is mainly due to the necessity of reducing a vast and ever-growing quantity of facts in a relatively short length of time. Obviously, the worry is that viewers who had not read the book would be at a loss to understand what is going on.