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Harry Potter and the Prisoner of Azkaban (2004) More at IMDbPro »

The following FAQ entries may contain spoilers. Only the biggest ones (if any) will be covered with spoiler tags. Spoiler tags are used sparingly in order to make the page more readable.

For detailed information about the amounts and types of (a) sex and nudity, (b) violence and gore, (c) profanity, (d) alcohol, drugs, and smoking, and (e) frightening and intense scenes in this movie, consult the IMDb Parents Guide for this movie. The Parents Guide for Harry Potter and the Prsioner of Azkaban can be found here.

Harry Potter and the Prisoner of Azkaban (1999) is the third book of the Harry Potter series, written by British author J.K. Rowling. The other books in the series include: (1) Harry Potter and the Philosopher's (aka Sorcerer's) Stone (1997), (2) Harry Potter and the Chamber of Secrets (1998), (4) Harry Potter and the Goblet of Fire (2000), (5) Harry Potter and the Order of the Phoenix (2003), (6) Harry Potter and the Half-Blood Prince (2005), and (7) Harry Potter and the Deathly Hallows (2007). Rowling's Harry Potter and the Prisoner of Azkaban was adapted for the screen by American screenwriter Steve Kloves.

There are eight movies in the franchise. In order, they are (1) Harry Potter and the Sorcerer's Stone (2001), (2) Harry Potter and the Chamber of Secrets (2002), (3) Harry Potter and the Prisoner of Azkaban (2004), (4) Harry Potter and the Goblet of Fire (2005), (5) Harry Potter and the Order of the Phoenix (2007), (6) Harry Potter and the Half-Blood Prince (2009), (7) Harry Potter and the Deathly Hallows: Part 1 (2010), and (8) Harry Potter and the Deathly Hallows: Part 2 (2011).

This is Harry's third term at Hogwarts. Towards the end of the movie, Professor Dumbledore refers to him as a 13-year old wizard.

Aunt Marge (Pam Ferris) was insulting Harry's parents. She accused his father of being a drunk, and then compared Harry and his mother to dogs, claiming "If there's something wrong with the bitch, then there's something wrong with the pup." As Harry admits later to Ron and Hermoine, he simply lost control.

By the rules, Harry could have been expelled from Hogwarts for using magic away from school or, even worse, he could have been imprisoned in Azkaban for breaking the law. However, the Ministry of Magic decided not to punish Harry because they knew that Sirius Black (Gary Oldman) had escaped from Azkaban and was looking to kill Harry. The Ministry was more concerned with keeping Harry safe from Sirius than with punishing him for performing magic in front of Muggles. Consequently, they resolved the problem by having the Accidental Magic Reversal Department cure Aunt Marge and erase the incident from her memory.

Returning are Professor Albus Dumbledore (Michael Gambon), headmaster of Hogwarts, Professor Minerva McGonagall (Maggie Smith), deputy headmistress of Hogwarts, head of Gryffindor House, and teacher of Transfigurations, and Professor Severus Snape (Alan Rickman, head of Slytherin House and Potions Master. In addition, we are introduced to Professor Sybil Trelawney (Emma Thompson), teacher of the Art of Divination, and Professor Remus J. Lupin, temporarily-appointed as the new teacher of the class in Defence Against the Dark Arts. Rubeus Hagrid (Robbie Coltrane) is back, newly-appointed to a teaching position in Care of Magical Creatures. Argus Filch (David Bradley), Hogwarts caretaker, is also there. There is a new music teacher, name not given, played by Warwick Davis, who did Flitwick in the first movie.

Richard Harris passed away in 2002 from Hodgkin's Disease. Other actors who were considered for the role of Professor Albus Dumbledore, Headmaster of Hogwarts, were Christopher Lee, Ian McKellen, Peter O'Toole, and Richard Attenborough before Michael Gambon was finally cast in the role.

Mr. Weasley (Mark Williams) explains to Harry that Sirius Black is a faithful servant of the evil Lord Voldemort. According to Mr. Weasley, when Harry thwarted Voldemort 13 years ago, Sirius lost everything. Now, Sirius believes that Harry is the one thing standing in the way of Voldemort's return to power, and the Ministry thinks Sirius has escaped from Azkaban in order to find and kill Harry. Later in the movie, Harry overhears Professor McGonagall describe how Sirius betrayed Lily and James Potter when they learned that they were marked for death and went into hiding, and he also destroyed their good friend, Peter Pettigrew. On top of all of this, Sirius Black is Harry's godfather. At the end of the movie, however, we find out that none of this is true, except for the last part.

In Divination class, Professor Trelawny looks at Harry's tea leaves and jumps back in horror, telling him that he has "the Grim". The Grim refers to a giant, spectral dog that is said to be an omen of death. During the Quidditch match, Harry does see a large, spectral dog in the clouds, so it appears that Professor Trelawny's divination is true. Later in the movie, it is made known that the Grim is Sirius Black. The Grim is no doubt patterned after the Black Dog, a prominent creature in British folklore, where the Black Dog is often said to be associated with Death and the Devil.

Hermione (Emma Watson) explains, while in Defence Against the Dark Arts class, that an Animagus is a witch or wizard who can choose to transform at will into an animal, as opposed to a werewolf who has no choice.

No. It is a complex skill that can take up to five years to learn. Because there is a huge risk of abuse of the ability, plus its complexity, the Ministry of Magic tries to regulate it. One has to register their ability, what animal they become, distinctive markings, etc. There are only a handful of people who have registered as animagi in the past century. The animal one becomes reflects one's qualities: James Potter becomes a stag, associated with honour and nobility; Sirius a dog, loyalty but also aggression and foolishness; Pettigrew a rat, dirt and disease; Prof. MacGonagall a cat, superiority and observance.

The explanation for this didn't make it from the book to the film. This is how it happened in the book: For twelve years, Sirius stayed in prison, probably out of some guilt due to being the one who suggested Pettigrew be the Potters' secret keeper, something that led to their death, or possibly because he thought Pettigrew was dead and knew that he couldn't prove his innocence without him. Sirius was able to retain his sanity against the Dementors, owing to the fact that he knew at all times that he was actually innocent: this was not a happy thought, so the Dementors could not seize it. Then, one day, the Minister for Magic visited and left Sirius a copy of the Daily Prophet (a wizard newspaper). In it was a story about the Weasleys winning some money and using it to go to Egypt. In the picture was their pet rat Scabbers - Sirius recognised Scabbers as Peter Pettigrew in rat form. From the article, he noted Ron was friends with Harry Potter and that they went to Hogwarts, and so he realised that he had to escape to protect his godson Harry. As an Animagus, Sirius could turn into a dog. Dementors don't have eyes; they sense people instead. Since most people become less human in Azkaban, sensing Sirius as a less-than-human dog was not unusual for them. As a dog, Sirius slipped through his prison bars and swam back to Britain.

Azkaban Prison is located somewhere in the North Sea, off the eastern coast of England [noted in The Half-Blood Prince]. A map of England showing the location of the North Sea can be seen here.

In the various books, the Dementors are described as floating, soaring, and swooping. This indicates to many readers that, yes, Dementors can fly. Granted, over short distance they tend to hover and float. And yes, in the books they stay on the pitch below Harry while he plays Quidditch and affect him from there, but that does not work so well visually. It was a creative decision to add to the impact of the visual medium.

In the books, Hogwarts students wear proper wizarding robes all the time, even out of lessons (except during holidays). In the first two films, director Chris Columbus made the decision that modernday kids wearing wizarding robes wouldn't work, so he gave them school uniforms with cloaks. They wore these during the school day; in the evenings, they wore their normal muggle clothes. Alfonso Cuarón, director of Prisoner of Azkaban, has kept with this idea. However, more action in this movie takes place outside of lessons, so it may seem to some like they aren't wearing their robes, but they are.

"...who explained the Grim?" He was some random guy. Depending on varying stories, he either won a competition or Alfonso Cuaron randomly picked him to deliver the lines. He doesn't correspond to any character in the books, and he is not Dean Thomas.

"...with Draco?" Another random 'Slytherin boy'. He was positioned as an extra henchman for Draco Malfoy (Tom Felton) when Josh Herdman, who plays Goyle, suffered an injury. In the Care of Magical Creatures class where we meet Buckbeak the Hippogriff, the sling on Goyle's arm can be seen when they tease Harry.

A Hippogriff is a legendary creature, a cross between a horse and a griffin. Like a griffin, it has the head of an eagle, claws armed with talons, and wings covered with feathers, the rest of its body being that of a horse. A photo of Hagrid's hippogriff, Buckbeak, can be seen here.

The Marauder's Map was given to Harry by George (Oliver Phelps) and Fred (James Phelps) Weasley, who stole it during their first year at Hogwarts. The map provides a detailed layout of Hogwarts, including hidden passageways, and shows where everyone is at all times.

The four creators of the Marauder's Map were actually Remus Lupin ("Moony", a werewolf) Harry's father James ("Prongs", a stag Animagus), Harry's godfather Sirius Black ("Padfoot", a dog Animagus), and Peter Pettigrew ("Wormtail", a rat Animagus). However none of this is used in the film which creates a plot hole with the following films due to Harry knowing who Wormtail and Padfoot are.

While they were all Gryffindor students at Hogwarts, Lupin used the excuse of his mother being ill when he disappeared each month (he was afraid they wouldn't want to be his friends if they knew). Eventually, they found out. Instead of abandoning Lupin, they all developed the ability to become Animagi.This had several benefits: werewolves are no threat to other animals, only humans, so in their animal forms they were safe. James could turn into a stag and Sirius into a big dog, so they could restrain the werewolf if he tried to get loose. Peter, as a rat, could sneak past the branches of the Whomping Willow and press the knot which paralysed it.

Lupin was bitten by Fenrir Greyback, a werewolf, when he was a child. Fenrir was in wolf form when he bit Lupin, meaning that the werewolf abilities were transferred to young Lupin.

Hermione: according to the book, Hermione has to defeat a Boggart during her final exams, and it turns into Professor McGonagall telling her she failed all of her tests.

Professor Dumbledore: according to J.K. Rowling, his Boggart takes the shape of his deceased sister.

Lord Voldemort: according to J.K. Rowling, a Boggart would take the shape of Voldemort's own corpse, given that he only fears death.

Yes, Dumbledore knew. As a young student of magic, Lupin found it hard to find a school that would take him, since he was a safety risk. However, Dumbledore agreed to take him as a student and then as a professor, with certain conditions. Every full moon Lupin had to stay in a shack in Hogsmeade. There was a tunnel going from the school to the shack, and to prevent the werewolf from coming out and to prevent students from going in, the Whomping Willow tree was planted over the entrance. Since Lupin's transformations were painful, locals heard shrieking coming from the shack, and rumours of it being haunted were started. Dumbledore encouraged this to keep Lupin's werewolf condition a secret. When Lupin was hired to teach Defence Against the Dark Arts, Dumbledore had Professor Snape mix up a concoction called the Wolfsbane Potion, which allowed Lupin to keep his human mind when he transformed -- he could simply curl up in front of the fire and wait to resume human form. He was to take the Potion during the week of the full moon and would miss classes the day after, with the other teachers pretending he was ill. He did not take the Potion on the night Sirius escaped as he forgot in his excitement after seeing Peter Pettigrew on the Marauder's Map.

A Patronus is a spell cast against Dementors (guards of Azkaban who feed on happiness, leaving a person with only misery and the worst memories of his or her life). The Patronus takes a form that represents a happy thought. To create a Patronus, a strong happy thought must be created, as it is happiness that chases Dementors away.

There are varying strengths of Patronus. Harry's first Patronus was weak and appeared as a misty shield. His second Patronus was fully corporeal and appeared as a white stag. A fully-formed Patronus usually takes the form of an animal and generally stays the same regardless of what the happy thought is, though it can change when one's source of general happiness changes, e.g. if you fall in love with someone.

Hermione possesses a Time-Turner, allowing her to turn back time. She is using it to take several classes all in the same time period. Professor McGonagall allowed her to use it to take extra classes. (Why she didn't simply tell Hermione to read the textbooks on her own time, instead of giving her an incredibly powerful and dangerous artifact, is unclear.)

JK Rowling has taken the route that there is no first time. What happened in the past cannot be changed; when you go back you just play your already determined role. Buckbeak never died, the executioner swung his axe in the pumpkin, the kids (and thus the audience) simply assumed he had executed Beaky. The idea is that any future time travel that may occur will already have affected events as they are now. I.e. in Bill and Ted their dad's keys are missing. They later decide that they will travel back in time, steal their dad's keys because they'll need them, thus the keys 'go missing'. Time travel is always confusing, but it does work with this theory. It does, however, pretty much take away Harry's free will. He has to go back to save himself because he already has.The answer to the question "What if he doesn't?" is simply that he can't not. In the HALF-BLOOD PRINCE book Rowling put in a line that all of the time-travel charms were destroyed during the battle at the end of ORDER OF THE PHOENIX. The line was not used in the HALF-BLOOD PRINCE movie, so it's a loose end as far as the movies are concerned.

Not exactly. Yes, in the books, the Seeker for Hufflepuff is Cedric Diggory. However, the character is not credited as such and is not played by Robert Pattinson (who plays Cedric in Goblet of Fire, where he has a much more integral role), so we have to assume not. The beginning of the next film also does not acknowledge this when they encountered Cedric and his father on their way to the Quidditch World Cup unlike the book which did.

The winner of the Quidditch Cup this term is not shown in the movie. In the book, the inter-house Quidditch Cup competition takes into account not just victories, but scores as well. Despite beating Slytherin in the first two books, Gryffindor failed to win the Cup. In Philosopher's Stone, the final match takes place while Harry is unconscious in the hospital wing after protecting the stone and Ravenclaw win the Cup. In Chamber of Secrets, the competition is cancelled because of attacks in the castle. The third year is Oliver Wood's final year (he's the one who explained the Quidditch rules to Harry) and he is desperate to win the Cup: in the book, Gryffindor win the Quidditch Cup. This was cut from the movie, for two reasons: 1) in the first movie, we see only one match, a win, and then see Gryffindor win the House Cup, so it would need a lot of explaining for their success to have the impact it has in the novel, and 2) n the grand scheme of the movies, it adds very little to the story being told.

It is revealed in the novel that he is one of its creators, nicknamed "Moony."

Harry's snowy owl: Hedwig

Ron's rat: Scabbers

Hermoine's cat: Crookshanks

Hagrid's Hippogriff: Buckbeak

No. Pettigrew escapes during the werewolf attack and is not seen again in this film. In the seventh book, he dies in fulfilling his "life debt" to Harry.

*Two Divination classes are shown: the first one of the year where Professor Trelawney reads Harry's tea leaves and the one where Professor Trelawney insults Hermione and she walks out of the class.

*Two Defence Against the Dark Arts classes are shown: the practical lesson with the Boggart & the one where Snape substitutes and teaches them about werewolves.

*The first Care of Magical Creatures class is shown although it is only Buckbeak there.

*One Dementor practice session with Lupin is shown.

After the Grim drags Ron and Scabbers down under the base of the Whomping Willow tree, Harry and Hermoine follow. They are confronted by Sirius Black and Professor Lupin. Hermoine reveals that she knows Lupin is a werewolf, and Lupin and Sirus together reveal the true story of how Harry's parents were betrayed by the fourth Marauder, Peter Pettigrew. Harry remembers seeing Pettigrew's footsteps on the Marauders Map, meaning that Pettigrew is still alive. Sirius forces Pettigrew (Timothy Spall) to reveal himself. Pettigrew, who is an animagus, has been hiding for the past 13 years as Ron's pet rat Scabbers, who was handed down to Ron by his brother Percy. The moon rises as they are on the way to returning Pettigrew to Hogwarts, and Lupin turns into a werewolf. When the werewolf turns on the children, Professor Snape shields them while Sirius, who is also an animagus, turns into the Grim and fights off Lupin. Pettigrew turns himself back into Scabbers and scampers away. When Lupin hears a howl of another werewolf, he runs off, but Sirius is seriously injured. Harry finds him lying next to a pool of water. The Dementors show up and attempt to steal Sirius' soul. Harry attempts a Patronus spell, but it isn't strong enough. Suddenly, Harry sees a white stag across the pool, whom he believes to be his father. The stag's presence drives away the Dementors. Unfortunately, even after Harry, Hermoine, and Ron vouch for Sirius' innocence, the Dementors intend to destroy him. Consequently, Professor Dumbledore, who also believes that Sirius is innocent, suggests that Hermoine use her Timeturner. Hermoine gives the Timeturner three spins, setting them back three hours.

Hermione's Timeturner takes them back three hours, just before the execution of Buckbeak, Hagrid's Hippogriff. Keeping themselves out of sight, Harry and Hermoine are able to lure Buckbeak out of the pumpkin patch by tossing him dead ferrets. With no hippogriff to execute, the executioner is sent away. They then go to the Whomping Willow tree where they wait until Lupin turns into a werewolf. Hermoine fakes a werewolf cry, causing Lupin to abandon his fight with Sirius. Unfortunately, the werewolf takes after Hermoine and Harry. They try hiding behind a tree, but Lupin spots them. Just as the werewolf is about to attack them, Buckbeak intervenes and sends Lupin high-tailing away. Harry looks up to see the Dementors flying overhead, so they race to the pool and watch as the Dementors take Sirius' soul. Fully expecting his dad to show up as the stag, Harry is surprised when he doesn't. So, Harry the time-traveler casts another Patronus spell. This time it works, but it is obvious to Harry that the white stag was not his father but Harry himself. Buckbeak flies them both back to Hogwarts where Hermoine releases Sirius from jail. Sirius invites Harry to come live with him, but asks him to wait for a while because his life is going to be a bit hectic at first. Sirius then flies off on Buckbeak, and Harry and Hermoine get back to where they were three hours ago in the infirmary, just in time for Ron to see their old selves disappear and their new selves show up across the room.

When word of Lupin's condition gets out, Lupin is compelled to resign his position at Hogwarts. Before he leaves, he returns the Marauder's Map to Harry. At the end-of-the-term feast, Harry receives a gift...a new Firebolt broom, the fastest broom ever made. (His old broom was destroyed when he was attacked by the Dementors during the Quidditch game.)

Without credits: 2 hours and 10 mins. With credits: 2 hours and 22 minutes; so the credits are about 12 minutes.

As with any film adaptation, there are differences from the novel. As was the case with the previous two Harry Potter movies, the time between events is often compressed as compared with the book, scenes and dialogues from the book are shortened or combined, and some scenes placed elsewhere in the narrative. Beginning with this film, the Harry Potter films begin to take more liberties, make more adjustments, and more cuts into (subplots of) the story. For example: the previous films showed Harry in almost all of his classes, whereas this movie has relatively few of such scenes. The following lists describes the largest deviations from the plot:

In the novel, Harry celebrates his birthday alone at the Dursleys' house. After a failed attempt to congratulate Harry by telephone, Ron and Hermione send him presents by owl post. Ron gives Harry a Sneakoscope, a device that warns the owner when an untrustworthy person is in the vicinity, and announces that he and his entire family have won money in a contest, and are going on a holiday to Egypt.

Aunt Marge stays for an entire week, annoying Harry with her concescendance. Harry assumes the name of his classmate Neville Longbottom when he is on the Knight Bus. There he learns that Sirius Black was convicted of killing 13 people with a single curse. Harry tries to get Cornelius Fudge to sign his permission slip to enter Hogsmeade, but Fudge refuses.

Harry spends some days at the Leaky Cauldron, where he learns that seeing a large black dog is an omen of death. His classmates arrive, and Hermione buys Crookshanks in a pet shop after the cat tries to attack Ron's pet rat Scabbers. In the train, Harry's Sneakoscope already starts to alarm when they sit next to Lupin (an early sign that Lupin is hiding something), but they dismiss the device as defective. The memory that Harry relives each time a Dementor is close becomes much more detailed with every iteration: he can clearly hear both his parents' final words before they are murdered. During the trip from the train to Hogwarts, Ron and Harry notice that the carriages are pulled by something invisible (explained in Harry Potter and the Order of the Phoenix). At Hogwarts, McGonagall shows concern for Harry's health after the Dementor incident, but he dismisses her wish for him to be admitted to the hospital wing.

The novel gives descriptions of each of Harry's classes, all the way up to final exams. This has been cut down a great deal in this film, so that we merely get an introduction to each of Harry's new teachers: Hagrid, Trelawney, and Lupin. Professor McGonagall immediately dismisses Trelawney's powers, as the latter has mistakenly predicted an impending death several times. There are several Hippogriffs shown during Hagrid's lesson. After the lesson, Harry, Ron and Hermione find Hagrid drunk and miserable, convinced that the incident with Draco and Buckbeak will get him sacked; his classes become much less fun afterwards.

As Harry isn't allowed into Hogsmeade, Lupin invites him for tea. The Lupin in the movie makes it clear that he knew Harry's mother, something only hinted at in the book. Snape enters and hands Lupin a potion, which he subsequently drinks, despite Harry's objections. The Fat Lady goes missing for several days after Sirius Black attacks her portrait; sir Cadogan, an inept knight, takes her place at the entry of the Gryffindor common room. Following the incident, Harry notices that all teachers start to get extremely protective of him.

Quidditch, a highlight of the previous films, gets only a cameo appearance in the movie. Harry is shown in only the first game against Hufflepuff, which incidentally introduces their new Seeker, Cedric Diggory, in the book. The book features the two subsequent games as well, after which Gryffindor, for the first time in years, wins the Quidditch cup (they lost it in the previous books because Harry was hospitalized (Philosopher's Stone) or the game itself had been suspended (Chamber of Secrets)). The second match incidentally introduces Cho Chang, Ravenclaw's new Seeker (as well as an important character in the next two books).

Two of Harry's unauthorized visits to Hogsmeade are combined in the film. During the first, Harry (hiding underneath a table to avoid being seen), Ron and Hermione overhear Cornelius Fudge talking to a few Hogwarts Professors about Sirius being Harry's godfather, James and Lily Potter's friend, as well as their Secret-Keeper; the latter role involved a complex spell, causing the Potter family's secret location to be completely invisible to anyone but Black and to those he disclosed the information to. Since Voldemort knew exactly where to find the Potters, this is considered proof that Black betrayed them to Voldemort. Apparently, Peter Pettigrew had confronted Black with this, only to be killed by Black together with 12 innocent Muggles, earning him a life sentence in Azkaban. In the film Harry heard the conversation by himself while under the Invisibility Cloak.

Harry is consumed with rage over this news, that was apparently withheld from him for years. He plans on confronting Hagrid about it, but Hagrid is in tears over the news that Buckbeak is likely to be executed following the incident with Draco. Harry calms down and promises to see if they can find legal grounds to get Buckbeak exonerated.

A Christmas dinner is organised for the teachers and students who remain at Hogwarts over the holidays. Ron and Harry learn that Lupin is 'sick' again and receives Snape's potions regularly. The Quidditch subplot also introduces Harry's new broom, the Firebolt, much earlier in the story. Harry actually receives the new broom before dinner, and Hermione immediately (and correctly) guesses that Sirius Black sent it. That there appears to be nothing wrong with it may be Rowling's first hint that Black is not the villain he's been made out to be. Unfortunately, the teachers find it highly suspicious, and immediately confiscate it for thorough examination, taking weeks before Harry gets it back. Ron and Harry are furious with Hermione, who apparently warned the teachers about the broom.

This, and the Marauder's Map (especially its shady origins and potential danger) causes the boys' relationship with a sceptic Hermione to cool down significantly. It is worsened by the increasing tension between Ron and Hermione over Crookshanks, who keeps targeting Scabbers. During one of these attacks, Harry's Sneakoscope sounds, another ignored hint that someone (in this case Scabbers) is not what he seems to be. A bloody sheet with Crookshanks' hairs on it temporarily ends their friendship. While this subplot is mainly cut from the film, some of Ron and Hermione's initial arguments were used, though they were not as serious compared to the book.

Harry has several unsuccessful lessons with Lupin in mastering the Patronus charm. During one, he learns that Lupin started at Hogwarts in the same class as Sirius Black, and that the Womping Willow was planted in their first year. Harry finally succeeds with the Patronus when the Dementors again show up during the second Quidditch match; however, these 'Dementors' are quickly revealed to be Draco and his friends in disguise, in an attempt to scare Harry into losing the match. That same night, there is another 'attack' by Sirius Black, directed at Ron's bed; Black apparently found a list of passwords for the dormitory that was lost by Neville (who receives severe punishment).

During Harry's second secret visit to Hogsmeade, the invisible Harry throws mud at Malfoy, Crabbe and Goyle, resulting in Malfoy seeing Harry's head and reporting him to Snape, who catches Harry sneaking back into school. Before Snape confiscates the map and gives it to Lupin, Harry confronts Snape with a rumour he heard in his first year, namely that Snape resented Harry's dad due to a life debt. Snape retorts that James once put him in considerable danger, but saved him, not out of care for Snape's life but of fear for getting expelled. In the movie, Harry throws snowballs at Draco and his cronies at Hogsmeade and Harry loses the Map to Snape when the latter catches him looking for Peter Pettigrew (which is not in the book) instead since Draco did not find out that Harry was in Hogsmeade illegally in the movie, though like in the book Lupin does take the Map into his possession.

Buckbeak's sentence and Hermione punching Draco in the face occur much earlier in the book, which brings the trio back together and renews their friendship. During final exams, a final appeal for Buckbeak is scheduled at school, but since this is also the day of his execution, the appeal is mainly a futile formality. Despite Hagrid urging them to stay away, the three use Harry's Invisibility Cloak to comfort him. In Hagrid's hut, they find Scabbers hiding (in the movie, Hagrid had found him).

During the confrontation with Sirius Black, Lupin mentions he followed Black to the Shrieking Shack with the Marauder's Map; this is also how he identified Scabbers as the supposedly deceased Peter Pettigrew. The novel also goes into more detail about Sirius' and Lupin's backstory: the Shrieking Shack was actually built to house Lupin as a student, each month as he transformed at the full moon. The Whomping Willow was planted to protect the underground entrance to the Shack, with a special trick to avoid the tree's branches. His friends, James Potter, Peter Pettigrew and Sirius Black all became Animagi (adopting the nicknames Prongs, Wormtail and Padfoot), so they could accompany Lupin ('Moony') when he transformed. Together they also created the Marauder's Map. Sirius decided to play a cruel and dangerous trick on an already suspicious Snape by telling him that he could find out Lupin's secret by going to the Whomping Willow. James, knowing Snape could be killed if he met the Werewolf, kept Snape from doing it. Snape still figured out that Lupin was a werewolf, and remains convinced to this day that James only warned him to save himself and Sirius from expulsion. With Snape's potion, Lupin is now able to undergo the transformations while retaining his human mind, rendering him harmless and suitable to teach (but in the exitement over Peter Pettigrew, he forgot to take his current dose).

Pettigrew's backstory is more elaborate: Sirius had suggested to make Pettigrew the new Secret-Keeper, and then found out that Pettigrew had betrayed the Potters. Sirius cornered Pettigrew, but the latter fired the Curse that killed 12 Muggles, and faked his death by cutting his own finger and escaping in rat form during the mayhem. Sirius was innocently sentenced to death, but felt guilty anyway, because he had suggested Pettigrew as the new Secret-Keeper. He kept himself sane by turning into his dog form regularly, a state in which the Dementors affected him much less. But when he saw a newspaper with a picture of the Weasley family after winning their contest, he recognized Scabbers and escaped. He stayed around Hogwarts, even being helped inside by Crookshanks (who stole Neville's password list), the only one who also recognized Scabbers as a fake. Pettigrew again faked his death and hid in Hagrid's cabin. After returning to human form, Pettigrew denies everything and still tries to put the blame on Black, but his lies are easily disproven. He is scared to death to go to Azkaban, mostly because he was the one to send Voldemort to his unexpected demise, and therefore fears the wrath of the remaining Death Eaters.

Hermione is present and affected during the Dementor attack on Harry and Sirius (but not when Harry finally conjures the full Patronus). The Dementors try to perform the Kiss on Harry as well. In the hospital wing, no one believes Harry's story since Snape claims that Black had used a Confundus charm on him, and Cornelius Fudge is all too willing to believe this easy explanation rather than admitting that Black was innocent all those years. Later, Snape goes as far as accusing Harry of helping Sirius escape, but he has no proof of this.

Harry's final talk with Lupin in the movie is a mix of two conversations in the book, with Lupin and Dumbledore respectively. Dumbledore also notes that Professor Trelawney had actually made a correct prediction, which happened only once before (an allusion to a revelation in Harry Potter and the Order of the Phoenix). He also mentions that Pettigrew now owes Harry a life debt, since Harry prevented Sirius from killing him (becomes an important point in Harry Potter and the Deathly Hallows).

Everybody passes the exams at the end of school year, and Gryffindor wins the House Cup, largely due to winning the Quidditch games. Hermione has dropped a few subjects and got rid of her Time-Turner. During the train ride home, Harry gets a package from Sirius, containing a signed Hogsmeade permission. The owl delivering the message is for Ron, since Ron no longer has a pet anymore. After arriving at the station, Harry entrusts uncle Vernon that he has a homicidal godfather, hoping it will scare the Dursleys into treating him better.