BookTok’s biggest sensation has officially blossomed to the big screen.

It Ends With Us, the adaption of Colleen Hoover’s book starring Blake Lively, Justin Baldoni and Brandon Sklenar, finally hit theaters on Aug. 9. And since becoming a smash sensation on TikTok in 2021, many have been wondering how the film would stack up to the best-selling book.

Originally published in 2016, It Ends With Us tells the story of Lily Bloom (played by Blake in the film), as she navigates a complicated, abusive relationship with a charming neurosurgeon named Ryle (Justin) and reconnects with her teenage love Atlas (Brandon). 

The novel oscillates back and forth between Lily’s present, as a 23-year-old starting a flower shop business, and her difficult teenage years—including dealing with an abusive situation at home—when she helped Atlas in a time of need. 

And the film has earned Colleen’s seal of approval as the author called it a “faithful” adaptation, noting she made sure the new movie stayed true to what fans hoped it would be—and what she wanted, too.

“After watching the movie and writing these roles,” Colleen told E! News last month, “the casting is so spot-on and everything I was hoping this movie would turn out to be.”

But that’s not to say the film is a beat for beat retelling.

"With every adaptation, things have to change,” she added. “You're trying to condense this whole storyline into a film, so there were some changes to make the flow better.”

The changes don’t necessarily mean for the worse, either. One major thing that Colleen noted the movie has over the book? A “phenomenal” Blake. 

“With the subject matter and the emotions of this book,” Colleen noted, “it needs that comedic levity, and she does it so well.”

Still, there are some changes that make the movie a bit different than what readers may expect. Want to see them all? Just keep scrolling.

*Warning: It Ends with Us Spoilers ahead*

For die hard It Ends with Us fans, this one was a controversial change. In the book, Lily is supposed to be 23. While no one’s age in the movie is explicitly said, it’s understood that the movie jumps ahead a bit.  

This was evident to fans once It Ends With Us cast Blake Lively, in the main role, along with Justin Baldoni—also the film’s director—and Brandon Sklenar, who were all in their thirties at the time of casting. Still, the author was on board with the shift—especially when it came to Ryle’s profession as a neurosurgeon. 

Believe it or not, Ellen Degeneres—yes the comedian and former daytime talk show host—plays a huge role in the book. In fact, Lily Bloom journals by way of fan letters to Ellen or “The Ellen Diaries”—and that’s how the readers find out what exactly went down with Lily’s mom and dad, as well as how she meets Atlas.  

While the film pays subtle tribute to the book’s recurring Ellen theme, featuring a brief shot of Lily’s journal with a page beginning with, “Dear Ellen” and even a brief clip from The Ellen DeGeneres Show in one scene, the comedian isn’t nearly as big of a deal in the film.  

One more missing homage to Ellen? Her famous line in Finding Nemo, “Just Keep Swimming,” is something Lily often repeats to herself during tough moments throughout the book—which Atlas also references during the very last line of the book. Finding Nemo does get a small nod as well though, as the film’s poster hangs on the wall of Lily’s teenage bedroom at the beginning of the film. 

In the movie, Lily’s eulogy for her father becomes a recurring motif for her relationship with him throughout the film. The “five things” Lily loves about her father (which are all left blank) are scribbled on a napkin, which she ultimately places on his grave at the end of the movie.  

However, the way it plays out on screen isn’t exactly how it happened on paper. Lily—whose eulogy is largely absent—doesn’t rush out of the funeral like she’s got to go somewhere a-la Gossip Girl’s Serena Van Der Woodsen (although who better to pull that off than Blake). Instead, she stands up there, intentionally silent, for several minutes before she is forcibly removed by a family member. The napkin momento is also a new addition to the film. 

Although they'll learn of his ability to cook, cinema viewers will miss out on Atlas’ tokens of gratitude to Lily. In the book, it seems Atlas’ love language is very clearly gift giving as he gives Lily a Boston keychain for her birthday as teens—which she holds onto even after they lose touch and later, it causes a fight with Ryle.  

And in another book reference to Ellen, after reconnecting as adults, he gives her a signed copy of the comedian’s Seriously…I’m Kidding featuring a message from the author. In the inscription, Ellen writes, “Lily, Atlas says to keep swimming.” 

Ellen wasn’t the only character whose screentime got scrapped. Lily’s mom also plays a much smaller part in the film than she does in the book. For one, her mother is supposed to follow Lily to Boston, and spends quite a bit of time with her daughter in the novel, whereas in the movie, she’s only included in a few scenes.

And though only in the book during one scene, Ryle’s mother—who lives in England—is also missing from the movie. Other minor players in Lily’s life that are not featured in the film adaptation include Lily’s roommate Lucy—who moves out but does end up getting a job at her flower shop in the book’s sequel It Starts With Us—and Lily’s former colleague, Devin, who attends Allysa’s birthday party with Lily (and temporarily pretends to be her boyfriend to make Ryle jealous).

Atlas’ restaurant coworkers Brad, Darin and Jimmy—who play poker with Lily in one scene—are also cut.  

The film’s handling of domestic violence is a major difference from the books, even having scenes play out differently altogether. In the novel, when Ryle burns his hand, he doesn’t push Lily down until he’s trying to cool it off under the sink—whereas in the movie, it happens right after he touches the hot surface. 

Throughout that scene in the book, Lily is also supposed to be uncontrollably laughing from intoxication (until Ryle turns violent). “Goddammit, Lily,” Ryle tells her in the book. “It’s not funny. This hand is my f--king career.”

And after he pushes Lily down the stairs in the book, she kicks Ryle out of the apartment—which leaves him to sleep in the hallway all night.  

The conversations surrounding abuse also play out differently in the film. For starters, Ryle doesn’t learn about Lily’s family history of domestic violence until after they’ve been dating a while in the movie but in the book, it happens on the first night they meet.  

A new addition to the movie is a poignant conversation between Lily and her sister-in-law Allyssa (Jenny Slate) after she finds out about Ryle’s abusive behavior and tells Lily about Ryle accidentally shooting his brother as children. In the book, it’s Ryle who explains to Lily how his brother died, and Allyssa never tells Lily she shouldn’t take Ryle back due to his abusive behavior. 

Although it’s a similar sentiment, Atlas’ restaurant, Root,  is actually called Bib’s—which stems from Lily and Atlas’ teenage catchphrase “Better in Boston"—in the book. The minor change allows the audience who has not read the book to understand just how much Atlas loves Lily, as Colleen noted. 

“It stood for something in the book that became a big thing for Lily to show how much she meant to him,” Colleen explained to E! News of the original restaurant name. “So that changed to Root in the movie because we didn't have as much time to put in all of the things that happened in the book to make that significant moment happen in the movie.”

Of course, the name Root does relate to a conversation that happens between Lily and Atlas in the movie, which is something Lily writes to Ellen about Atlas in the book. 

“Some things, like trees, are strong enough to do it by just relying on themselves and nobody else,” Lily explains, noting she could tell Atlas was “resilient—way more than I would ever be if I were in his situation.”

Although it is serendipitous, Ryle and Lily get married in front of Allysa, her husband Marshall (Hasan Minhaj) and their parents in the book. The movie glosses over the milestone a bit more quickly, but—unlike the movie—Lily’s mom was there in the book, and they likely spent a ton of money on cross country late night flights to Nevada.

In the book, Lily names her and Ryle’s baby Emerson Dory—a nod to both Ryle and Atlas as Emerson is the name of Ryle’s late brother and Dory is a nod to her and Atlas’ shared love for Ellen DeGeneres.

The movie, however, only shares “Emerson.” And while Allysa and Marshall welcoming their first baby does take place in the movie, it makes no mention of naming her Rylee after Allyssa’s brother Ryle. 

The characters may be dressed a little differently than what readers had in mind. In fact, It Ends With Us got some pretty serious backlash after photos of the costumes on set went viral. However, the novel rarely describes clothing aside from generally such as Ryle’s scrubs or Lily’s “baggy sweater.”

As for what Colleen had to say about the backlash? 

 “I don't remember describing outfits at all,” she told Today. "I don't care what they have on. In my head, it's about the conversation they're having and the story. It's the same way in the movie.” 

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