Screenwriter Christy Hall tells PEOPLE how she was able to “very respectfully modernize” an emotional scene between Lily and Atlas from the 2016 novel

Note: This article contains spoilers for It ends with usnow in cinemas.

Lily’s discovery that she is pregnant with Ryle’s child is one of the most emotional scenes in It ends with us, both in Colleen Hoover’s 2016 book and in the new film adaptation. However, the plot is presented subtly differently on screen.

A hospital visit with Atlas (Brandon Sklenar) after Ryle (Justin Baldoni) attacks Lily (Blake Lively) leaves her deeply shaken when she learns she is pregnant. Atlas then takes her to his home so she can rest and recover. There she expresses her fears about motherhood and he says if she chooses to go for it, she will be a great mother.

The commentary is brief, but the film’s screenwriter Christy Hall told PEOPLE it was “important” to her to include it.

“I think the novel is absolutely perfect, but it was also written a few years ago, so there were opportunities to modernize it with a lot of respect,” she says.

Related: It ends with us: The biggest differences between Colleen Hoover’s book and the Blake Lively film

“In the book, the pregnancy is talked about in a way where everyone automatically assumes she’s going to get it and keep it. The way Atlas talks about it, the way Ryle talks about it, the way even Lily thinks about it, it’s already automatic,” Hall says.

“No one ever asks a question. It’s automatic: ‘Well, it’s quite clear what you’re going to do,'” she adds.

Related: Blake Lively and Jenny Slate Break Down Their Emotions It ends with us Scene: “I was drooling” (Exclusive)

The screenwriter who most recently wrote the screenplay and directed Papadioadds: “There are a lot of different nuances in what Atlas is saying. And it just seemed important to me to acknowledge that it should be more of a conversation than just a pressured assumption without her even having a choice.”

The storyline of Lily’s pregnancy is a little different on screen than in the novel, and Hall says it’s ultimately about “real estate.”

“It’s a very dense book. I know it doesn’t look like it, but when you adapt it, you end up with a lot of substance, in a positive sense,” she explains.

The exact dynamic between Lily and Ryle after their argument and how Ryle finds out about Lily’s pregnancy is less clearly portrayed in the film, and that’s just another thing they had to “cut” to “really be considerate of (the running time),” according to Hall.

Luckily, Hall’s favorite scene from the book made the cut, which isn’t surprising since it’s when Lily and Ryle first meet. “The rooftop scene was probably the hardest because I think the rooftop scene fits perfectly into the novel,” she says.

Her first attempt at the scene was 10 pages long. “That’s probably the scene I spent the most time on. I really cut it down and really worked with Colleen to figure out what needed to happen in the scene and what didn’t need to happen.”

Never miss a story — sign up for PEOPLE’s free daily newsletter to stay up-to-date on the best of what PEOPLE has to offer, from celebrity news to compelling human interest stories.

At the film’s premiere in New York City, Lively said her husband, Ryan Reynolds, provided dialogue for the rooftop scene that opens the book. Hall says she was unaware of Reynolds’ involvement.

“There were a few little things that I thought were improvised. Like when (Ryle) says, ‘Please, please, with a cherry on top,’ and (Lily) talks about the maraschino cherries. When I saw a cut, I thought, ‘Oh, that’s sweet. That must have been a sweet improvised thing.’ So when I’m told that Ryan wrote that, that’s great, how wonderful.”

Ultimately, however, she says she is “very proud” of her work. “The moments that I felt deserved to be honored are there. So I recognize the scene and I’m proud of it. And if those flourishes come from Ryan, I think that’s wonderful.”

It ends with us is now in theaters.

Subscribe to our newsletter to receive more People news!

Read the original article on People.