'It Ends with Us' author Colleen Hoover says Justin Baldoni 'struggled a little bit' with idea of playing Ryle

Author Colleen Hoover knows better than anyone how passionate fans are about her bestselling book It Ends with Us. From the moment Blake Lively was cast as lead Lily Bloom in the film adaptation, the internet has had a lot of opinions without knowing much.

"At the beginning, I was kind of shocked that everyone was so passionate about the wardrobe," Hoover told Yahoo Entertainment, referring to how the internet picked apart paparazzi photos of Lively filming. However, Hoover said she quickly took that passion as a "compliment."

"I was like, wait — they're passionate about it because they read the book and they want it to feel the same as the book," she continued. "I look at it as such a compliment that readers are so passionate about it having the same [feeling] as when they were reading the book. And I really think they'll be happy once they go see it. I think that [the cast and crew] did the book such justice."

Screenwriter Christy Hall had the large task of adapting the book to the big screen. The rights were acquired by director Justin Baldoni, who also stars in the film as Ryle. According to Hoover, it was a bit of a process to convince him he should get in front of the camera to play Lily's troubled love interest.

"Justin actually bought the film rights for the book. He sent me a really lovely letter saying how much the book meant to him. And as we kind of went along in the process, he was like, 'Oh, I think I might wanna direct this," Hoover explained, noting she had just seen his 2019 directorial debut Five Feet Apart. "I watched it and I was like, 'Oh you did such a good job with that movie. I feel like you would do a good job with this one.' And then the idea of him playing Ryle came up. He struggled a little bit with like — can you take on all of these roles and do a good job? But as you can see, he pulled it off."

It Ends with Us is based on Hoover's parents' relationship. The romantic drama follows Lily, who overcomes a traumatic childhood only to find herself in an abusive relationship. The author believes Lively nailed the complexity of Lily.

"Actually seeing her in this role, I can't picture anyone else in this role. She just did such a phenomenal job bringing her to life and I couldn't be happier," she said.

With any book-to-film adaptation there will be some changes, but Hoover is happy with how much stayed the same.

"I really, really wanted the storyline to be extremely similar to the book and the characters. I was super excited when everyone made it in — Atlas and Lily and even Marshall and Allyssa and Ryle. Because sometimes [filmmakers] will take out a character completely," Hoover said.

But there was one thing that Hoover believes was a better change in the movie.

"One of the things that I didn't really mind that they changed was the name of [Atlas's] restaurant," she explained. "Like there wasn't a lot of time in film to put together all of the things that Atlas and Lily had in common from their childhood. And so changing the name from Bibs to Root, I feel was a necessary change for the film and a better one."

It Ends with Us is in theaters Aug. 9.