At 870 pages, "Harry Potter and the Order of the Phoenix" is the longest book in the series. And yet it's the shortest film, clocking in at two hours and 18 minutes. That doesn't happen without a lot of cutting and condensing.

"The danger with adapting the book to the film is that even non-'Potter' fans need to feel like they got it," director David Yates said. "They need the clarity. By removing some things, we allow a whole new audience in."

(See what a handful of hard-core "Harry" fans had to say about the latest flick.)

Hard-core fans won't miss much. The essence of "Phoenix" is still there — in fact, it's one of the most faithfully adapted of the "Potter" books to date. (Rupert Grint, who plays Ron Weasley, said that Yates "knew the books better than me.") And while some things have been taken out, a few others have been added that probably only fans will catch, like Ginny Weasley's reaction to the goings-on between Harry and Cho ("I couldn't help myself," Yates admitted with glee).

"All the background of the book is there," said Bonnie Wright, who plays Ginny. "You don't have to know what's happening before and after and why, but it's there."

Still, some fondly regarded subplots, clues and bridges to the next two installments are missing. Here are a few of them:

First, "Remember My Last"
In the book, as the Dursleys are about to kick Harry out after the Dementor attack, Aunt Petunia gets a Howler from Dumbledore that screams in "an awful voice," "Remember my last!" Harry is immediately suspicious. "Remember the last what?" he asks. And how does Petunia seem to know about Dementors and Azkaban, the wizard prison they guard? Considering she "usually put all her energies into pretending [the wizarding world] didn't exist," Harry wonders if she's been in touch with wizards after all.

"You might have got the impression that there is a little bit more to Aunt Petunia than meets the eye, and you will find out what it is," J.K. Rowling once said. "She is not a Squib, although that is a very good guess. Oh, I am giving a lot away here. I am being shockingly indiscreet." How indiscreet we can only guess, since the movie includes nothing that hints at Petunia's potential.

No Love For Lily?
And what about Petunia's sister Lily, Harry's mother? In the book, there's a glimpse of Lily as a teenager in a flashback that shows us "Snape's worst memory." We see Harry's father, James, tormenting the young Snape with curses that turn him upside down, revealing his graying underwear. Lily comes to Snape's defense, telling James she'd never go out with someone so cruel. Snape, however, snaps, "I don't need help from filthy little Mudbloods like her!"

Snape fans have theorized that it was his regret over calling Lily such a nasty name when she was trying to help him that makes this such a painful memory — not just his bullying at the hand of the popular James and his friends. They further theorize that it was Snape's tender feelings for Lily — not his dislike of James — that convinced Dumbledore that the prickly Potions teacher truly regretted helping cause her and James' deaths.

But in the movie, "Snape's worst memory" is cut short before Lily enters the scene. Does this mean fans have read the moment wrong? Not necessarily. "We had that in the cut at one point," Yates said. "We had a lovely actress playing Lily. But by introducing the Lily/Snape plot and that back story, we complicated it too much. We may bring her back for 'Half-Blood Prince.' "

Quidditch Ditched
Poor Ron — just as his character comes into his own by playing keeper for the Gryffindor team, his subplot gets scrapped (along with Hermione's efforts to free the house elves). Emma Watson still gets to move the story forward in other ways, but Grint is relegated to the role of Harry's protective sidekick. Why? Because Quidditch scenes weren't something the director felt this fifth movie needed.

"I love Quidditch," Yates said of the fictional sport. "I think it's the best thing in the world, but we've been there, done that. This is about fresh experiences, new places, new things." As for the missing save-the-house-elves plotline, Watson hopes it will be revisited at some future point. "I'd like to see Hermione protesting somewhere," she said. "Doing something for house elves."

Magical Maladies
Some scenes in the book still happen — they just happen offscreen. Take Arthur Weasley's trip to the wizard hospital, St. Mungo's, after he's been attacked. It's at this hospital that Harry's friends discover a ward housing Neville Longbottom's spell-damaged parents, who were tortured into insanity at the hands of one of Voldemort's followers. This is why Neville is so distraught at seeing a spider tortured with the Cruciatus Curse in "Goblet of Fire" and why he's emboldened, in "Phoenix," to sharpen his magic skills after learning that the Death Eater who cursed his parents has escaped from Azkaban.

In the movie, however, Neville simply tells the story of what happened to his parents. So the information is there, but not seeing it somewhat diminishes the impact. Neville, however, does get a few consolation moments in the film (like finding the Room of Requirement).

"I suppose we can't do everything," Wright said. "They were going to have St. Mungo's, and we still physically go there, but it's not shown in the film. That just has to do with the time that we have [in the movie]. Most of the really important stuff is connected. They can't cut things out that are crucial for future films."

Look, A Locket
Unless the filmmakers didn't know it's crucial. Rowling herself had to intervene on behalf of Kreacher, the house elf who lurks around the Order of the Phoenix headquarters at 12 Grimmauld Place, because he'll play an important role in book seven (see "Kreacher Comfort: MTV Solves A 'Harry Potter' Mystery"). Hmm. Could this be because he squirrels away artifacts such as, say, a mysterious locket no one can open? Potter fans think it's a Horcrux, but you won't see anything about that in the film.

"It was kind of tricky to raise that in our story, because it's for so much later," Yates said. "We figured we can probably introduce it later, and that's the approach we took."

Kreacher's role in the movie is now limited to muttering and mumbling — he's there, but just barely. We don't see how he helps betray his ostensible master — Harry's godfather, Sirius Black — but the tragic results are the same.

Let's Not Quibble
In the movie, we see Luna Lovegood reading The Quibbler upside down, but any mention of this alternative publication (which is run by Luna's father) ends there. "The Daily Prophet is the proper newspaper, and The Quibbler is like The National Enquirer," explained Yates' assistant, Jamie Wolpert, who plays a Prophet newsboy in the film.

"Some of the stories The Quibbler runs are a bit crazy, like Sirius Black being a successful singer, which is just not true," said Evanna Lynch, who plays Luna. "But they don't mean to make up things. They actually believe the things that they print."

"People are much more willing to believe what they read in the papers," said Daniel Radcliffe. "Even when they shouldn't, when it's being manipulated or running away with itself."

So when The Daily Prophet is pressured by the Ministry of Magic to start printing propaganda, it falls to the usually unreliable Quibbler to set the record straight via an exclusive interview with Harry about Voldemort's return, outing the Death Eaters in everyone's midst. "For once, it's printing the truth," Wolpert said. That interview helps win over Potter doubters, but the mass breakout from Azkaban serves the same purpose.

Cho Changed
Don't worry, we still get Harry and Cho's first kiss (see "Daniel Radcliffe Dishes On Harry Potter's First Kiss, 'Deathly Hallows' Theories") — but not their disastrous first date. So instead of the tension between them, there's the much anticipated tender moment, followed by a form of betrayal that, in the book, came from another character, not Cho. But it's not her fault.

Do I Have A Choice?
The big revelation in the "Phoenix" book is that there's a prophecy about a boy with the power to vanquish Lord Voldemort. It says, "Either must die at the hand of the other for neither can live while the other survives." Technically, the prophecy could mean either Harry or Neville, since both were "born to those who have thrice defied [the Dark Lord], born as the seventh month dies." But Voldemort decided it must refer to half-blood Harry instead of pure-blood Neville, which is what prompted him to try to kill Harry when he was a baby. This becomes a crucial point later on, as Dumbledore explains to Harry.

In the film, however, all of this is rushed through. We don't hear the whole prophecy, and we don't know who made it or whether it might have been overheard halfway through its original telling. This incomplete information puts us in the same boat as Voldemort, who didn't know that by attacking the baby Harry, he risked transferring some of his power to the boy. Dumbledore tries to tell Harry that the prophecy didn't become destiny until Voldemort came to believe it and thus helped fulfill part of it. Had Voldemort never heard about it, had he never acted on it, Harry never would have been in a position to be a threat to him — prophecies, it turns out, only work when you put stock in them. Perhaps all of this was too metaphysical to follow a fiery, climactic battle scene. But you can predict that more on it will come in "Half-Blood Prince."

Last, But Not Least
We don't want to spoil this, so we'll tread carefully here. In the movie, it's never quite resolved why the Dementors attack Harry and his cousin in a Muggle suburb. We're left to assume that Voldemort's behind it and that the Ministry has lost control of the Dementors. But the real villain in this instance, who reveals the truth in the book, doesn't self-incriminate in the film, so the subject is dropped. But be assured that the actor who plays this character still had that knowledge in mind during the filming of the movie. As he or she told us, "I don't think [he or she] thinks they're evil. [He or she] ordered that for the good, and that's what's frightening. [He or she] doesn't think, 'I'd better not do that, somebody might get hurt.' It's whatever it takes, and that's why it's so disturbing." Frankly, we think this character is disturbing enough. But that extra tidbit of knowledge tips him or her over the edge in our book.

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