The Twilight saga is one of the best-selling book and movie series of all time. While each movie adaptation of its respective book makes its own changes, Eclipse might be the one with the most alterations from the source material.

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Many of these changes are completely understandable since a movie only has about two hours to tell hundreds of pages worth of story. Some of the changes from book to screen arguably improved the story and the characters. But others left out some of the best parts of the book and raised debate amongst fans.

Bella Being Grounded

Edward and Bella in the meadow in Twilight

At the end of the previous book, Jacob brings Bella's motorcycle to her house so Charlie will see it and ground her. This punishment carries over to the beginning of the Eclipse book, and Bella can only see Edward for a limited amount of time at her house every day.

In the movie, she just has a really strict, early curfew. This allows for a cute opening sequence between Bella and Edward in their meadow.

Jasper's Fake Age

Jasper in Eclipse

In the books, Rosalie, Emmett, and Jasper pose as the elder Cullen siblings. This means that when Bella, Edward, and Alice are seniors, they've already graduated.

The New Moon movie changed this, and had Jasper stay in high school with Alice, Edward, and Bella. It's unclear why this choice was made, but for the sake of continuity, the change was maintained in the Eclipse movie.

Riley's Involvement

Riley glaring

In the book, there's no mention of Riley until Bella sees him during the final battle. The movie has the advantage of being able to depart from Bella's point of view, so we see a lot more of Riley's backstory. He's also connected to the main storyline a bit more, in that Charlie is investigating his disappearance.

This provides him and Bella with an opportunity to talk about how Charlie would feel if Bella went missing. Since much of Eclipse is about Bella contemplating becoming a vampire, this weighs on her and her decision.

Bella And Angela

Jessica, Eric, Angela, and Mike in the school parking lot

In the book, Angela is Bella's only good human friend. Of course, there's Jessica, Eric, and Mike, two of whom want to date Bella and one of whom doesn't seem to like her all that much.

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Angela is the only person besides Bella's parents who give her pause over her private contemplation about her future as a vampire since she's the only friend Bella would really be sad to lose. This plot was originally going to be included in the movie, but it was ultimately cut for time.

Bella Visiting Jacob

Jacob and Edward arguing over Bella

In the book, a huge deal is made out of Bella's desire to see her best friend, Jacob. She asks Edward for his blessing, and Edward tells her he won't let her see Jacob. He goes so far as to mess with her truck so it won't drive, which was included in the movie.

However, movie Bella goes ahead and leaves school with Jacob, and Edward doesn't do anything about it. It's possible that the movie didn't want to spend too much time on this point, or make Edward appear too controlling.

The Quilt

Bella and Renee smiling

In both the book and the movie, Bella visits her mother in Florida using the plane tickets Carlisle and Esme bought her for her previous birthday. The movie makes a nice addition to this, by having Renee give Bella an early graduation gift in the form of a quilt made out of all of the t-shirts she and Bella got on the many trips they took together when Bella was growing up.

It's shown again later in the films, and it's a nice reminder that Bella's mother is on her mind, despite not being featured onscreen very often.

Bella's Kidnapping

Alice smiling

In the book, Edward's obsession over Bella's safety leads to him asking Alice to kidnap Bella when he's away so that he can make sure she doesn't go and see Jacob. Alice picks Bella up from work and makes her cancel her plans to hang out with Jacob. During this "sleepover" at the Cullens, Rosalie tells Bella about how she became a vampire, and why she doesn't think Bella should.

The movie removes this story, likely for the sake of time and not wanting to make Edward too unlikable. In the movie, Rosalie tells Bella her story after Bella breaks her hand.

Charlie's Reaction To Jacob Kissing Bella

Bella and Jacob looking at each other in New Moon.

A source of debate in the book is Charlie's reaction to finding out that Jacob kissed Bella against her will. In the book, Charlie congratulates Jacob for essentially assaulting his daughter, something some fans have taken issue with, for good reason.

Luckily, the movie changes this. Though Charlie doesn't arrest Jacob or do anything drastic to signify his disapproval, he doesn't condone or endorse Jacob's action like in the book.

The Valedictorian

Jessica smiling

In the book, Eric Yorkie is a nerdy, academic type. His intelligence leads him to be named class Valedictorian.

The movie changes his character, making him more of a jokester and Jessica is the Valedictorian in the Eclipse movie.

Bella And The Rock

Bella hiding behind Edward

In the book, Bella is inspired by a story told at a bonfire she attended with Jacob. The story was about a human woman who sacrificed herself to save her husband, drawing her own blood to distract a vampire who was going to kill him. Bella becomes obsessed with the idea of helping in this way and uses a rock to open up an old scar during Edward's fight with Victoria. This frustrates Edward, as it was an unnecessary risk.

The movie makes this move a bit more integral to Edward's survival. Bella cuts herself just as Riley and Victoria are about to kill Edward, distracting them enough to save his life.

NEXT: 5 Ways The First Twilight Is The Best (& 5 Ways It's New Moon)