Harry Potter and the Order of the Phoenix is the longest book in the series. Because of this, it’s no wonder that there are many details from the book that weren’t able to make it into the movie. This is one of the Harry Potter movies where there are a lot of obvious differences between the book and the film. While the movie does a good job at focusing on the most important plot points and characters, there are still some things that won’t make a lot of sense for people who have only seen the movies.

Here are the ten things from Harry Potter and the Order of the Phoenix that only make sense if you’ve read the books.

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WHO MUNDUNGUS FLETCHER IS

Mundungus Fletcher talking in Harry Potter and the Deathly Hallows

Mundungus Fletcher is definitely not the most important member of the Order of the Phoenix, but his criminal ways are important to a few plot points from the book. In the movie, he is only mentioned briefly when Mrs. Figg finds Harry and Dudley after the dementor attack. In the books, it’s explained that he's a member of the Order and also an overall thief and crook. While he might not have been essential to include in the movie, the quote that mentions him doesn't make a lot of sense.

HOW TONKS CAN CHANGE HER APPEARANCE

Nymphadora Tonks is definitely an engaging and likable character even if she doesn’t get a lot of focus in either the books or the movies. One of the most interesting things about her is that she is a metamorphmagus. This means that she is able to change her appearance at will. In the movie version, audiences see her change her hair color, but there's no explanation for this. It just seems like this is something that many witches and wizards can do when really it’s a rare ability.

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PERCY’S CHANGE IN HOW HE ACTS TOWARD HARRY

One major point from the books that was cut in the film was Percy betraying his family and supporting the Ministry of Magic. This is a big point of contention and shows how the Weasleys are willing to give up a lot to support the Order of the Phoenix. In the movie, Percy’s demeanor is shown to have changed to be more cool towards Harry, but there's no explanation for this. This was one storyline that was just completely cut out.

WHY ARABELLA FIGG IS PART OF HARRY’S HEARING

Arabella Figg walking into a tunnel in Harry Potter and the Order of the Phoenix

Mrs. Figg seems to mostly come out of nowhere in this Harry Potter movie. However, in the books, she’s mentioned a few different times, and readers know that she used to babysit Harry when he was a kid. The books also explain that Mrs. Figg is a Squib, which is a non-magic person born into a wizarding family. This is how she knew to help Harry and why she was keeping an eye on him for Dumbledore. Since this isn’t explained, it seems a bit weird that she shows up to Harry’s hearing to defend him. It’s not very clear if she is a Muggle or not.

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WHAT THE ORDER OF THE PHOENIX IS ALL ABOUT

In the books, there are a couple of chapters devoted to being at 12 Grimmauld Place, which is the headquarters for the Order of the Phoenix. This gives readers a chance to see what is going on. They see members going in and out, and it’s clear there is a lot of activity in this organization. We also see Harry and the underage Weasley children cleaning out the house and getting rid of the dark magic and magical creatures that reside there. The books don’t really include any of this information as there just wasn’t time for it.

JUST HOW HORRIBLE UMBRIDGE WAS

Professor Umbridge

If there’s one thing that’s apparent in both the books and the movies, it’s that Dolores Umbridge is a horrible person. She’s extremely cruel and sadistic, and she punishes students using a form of torture. While the movies do a good job of showing her cruelty, the books go even more in-depth into this. For example, in the books, it’s made clear that Harry is subjected to multiple detentions with her. It’s so bad that he has a scar on his hand for years after.

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THAT UMBRIDGE WAS SURVEILLING COMMUNICATION IN AND OUT OF HOGWARTS

As High Inquisitor of Hogwarts, Umbridge was basically a dictator who had quite the authoritarian rule. She created dozens of Educational Decrees that made life at Hogwarts very strict. In the movies, it’s implied that she is watching students closely, especially Harry and anyone associated with Dumbledore, but the books make this even clearer. In the books, we see that she is tampering with all means of communication including owl post and the Floo Network.

WHY CHO WOULD BETRAY DUMBLEDORE’S ARMY

One thing that the movies do a bad job of is exploring the character of Cho Chang. In the movies, she’s the one who betrays Dumbledore’s Army to Umbridge. This doesn't even make much sense in the world of the movies since Cho comes back after to fight in the Battle of Hogwarts, which is quite the brave thing to do. The truth is that in the book it was Cho’s friend Marietta Edgecombe, who betrayed the DA, not Cho.

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THE IMPORTANCE OF PROFESSOR TRELAWNEY

Professor Trelawney seems mostly like an eccentric character used for comic relief in the movies, but she actually plays an important role in the books. Her prophecy, the one that Voldemort was so desperate to get his hands on, is not shown in the Department of Mysteries like it was in the books. Also, there isn’t even a mention in the movie that she was the one who told that prophecy.

WHY HARRY IS STRUGGLING SO MUCH

Hermione and Harry Order of the Phoenix

There is some hint that Harry is going through a rough time in the movie version of Order of the Phoenix, but it’s even clearer in the books. In the books, there is more exploration of the fact that the death of Cedric Diggory and the return of Voldemort has left Harry dealing with a lot of trauma. This is somewhat ignored in the movie version.

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