Spoiler alert! The following story contains major plot details about the "It Ends with Us" book and movie (now in theaters).

Blake Lively is back on the big screen.

The “Deadpool & Wolverine” actress has her first leading role in four years in “It Ends with Us," the hotly anticipated adaptation of Colleen Hoover’s 2016 novel. Like the book, the movie follows a flower shop owner named Lily Blossom Bloom (Lively), who falls in love with a dashing neurosurgeon named Ryle Kincaid (Justin Baldoni), and reconnects with her stoic childhood sweetheart, Atlas Corrigan (Brandon Sklenar). The romantic drama also features a star-studded supporting cast, with Jenny Slate as Ryle’s sister, Allysa, and Hasan Minhaj as his brother-in-law, Marshall.

Directed by Baldoni, the heart-wrenching film is a largely faithful retelling of Hoover’s book, grappling with the insidious nature of domestic violence and cycles of abuse across generations. Here are some of the biggest changes from page to screen:

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What's the biggest difference between the 'It Ends with Us' book and movie?

Perhaps the most significant change between the book and movie is in how Lily perceives Ryle’s abuse. Through a series of quick cuts and deceptive camera angles, the film plays on Lily’s uncertainties: Did Ryle actually mean to strike her after burning his hand, or was that just an accident? Did Lily merely slip on the stairs during an argument, or did Ryle deliberately push her? Lily is continually in denial until the movie’s final third, when a disturbing montage shows her husband's assaults as they really happened.

But in the book, Ryle's misconduct is not a gradual realization for Lily. Instead, she calls him out after each incident and warns him that she’ll leave the next time he abuses her. She first tries to leave him after her violent fall, but then chooses to forgive Ryle, who’s traumatized by his brother’s death. She reasons there is good in him, and that he can still change. But when Ryle later tries to rape her and she lands in the hospital, Lily decides she’s had enough.

Does the novel end differently than the film?

The book draws out Lily’s breakup with Ryle, as he flees to Europe for three months and she confronts him upon his return. (“I wish this baby wasn’t yours,” Lily says angrily, after he shows up at her apartment unannounced.) They eventually agree to divorce, and the novel ends with a scene of Ryle and Lily amicably co-parenting, just before she rekindles her flame with Atlas.

The movie ends on a similarly romantic note, as Atlas and Lily run into each other at a farmers market and decide to give romance another shot. But it also adds much-needed closure for Lily and her mother, Jenny (Amy Morton). Jenny endured a lifetime of abuse from her husband, and Lily resentfully tried and failed to eulogize her dad at his funeral.

Toward the end of the film, Lily and Jenny visit her father’s grave along with Lily’s young daughter, Emerson. After Lily leaves her blank eulogy notes on his tombstone, the Bloom family embraces and walks away. It’s a poignant moment for the three generations of women, signaling a fresh start as they leave their trauma behind them.

Does Ellen DeGeneres make a cameo in 'It Ends with Us?'

If you haven’t read “It Ends with Us,” you could never imagine what a huge role Ellen DeGeneres plays in the story. (Yes, really.) In the book, young Lily recounts her entire childhood in a series of journal entries addressed to the former daytime talk-show host. Lily and Atlas also remind each other to “just keep swimming” – a hopeful mantra by DeGeneres’ “Finding Nemo” character, Dory. As adults, Atlas even gifts Lily a signed copy of DeGeneres’ memoir, “Seriously … I’m Kidding.”

Wisely, the movie does away with the whole DeGeneres conceit. The comedian’s reputation has been sullied since “It Ends with Us” was published in 2016, and her talk show fizzled out amid scandal in 2022. Instead, Lily and Atlas’ high-school courtship is now told through a series of straightforward flashbacks.

Although, there is still one DeGeneres Easter egg in the film: The first time Atlas comes over to Lily’s house, she’s on the couch watching “The Ellen DeGeneres Show.”

Which book characters don't appear in the movie?

Streamlining the story from page to screen, a few memorable characters have been cut along the way. The film axes Devin, Lily’s gay BFF who makes Ryle jealous by pretending to be her boyfriend. There is also no Lucy, Lily’s former roommate who winds up working at her flower shop. Ryle’s mom and dad are missing from the movie as well: Instead of getting engaged at his parents’ apartment, Ryle now proposes to Lily in Allysa’s hospital room shortly after she gives birth. (Sorry, but did he really have to upstage his sister like that?)

How old are Lily (Blake Lively) and Ryle (Justin Baldoni)?

Fans of “It Ends with Us” were initially miffed by Lively’s casting. After all, Lily is described as having “red hair and fair skin” in the book, whereas Lively is unequivocally blond (a fact that the movie hardly disguises). Also, Lily is 23 and Ryle is 30 when the novel starts, while in the movie, both characters are in their mid-30s.

Baldoni and Hoover recently defended aging up the characters, saying it would naturally take a long time for Ryle to become a prominent board-certified neurosurgeon. They also wanted Lily to be someone with life experience, who is comfortable and confident in herself by the time she meets Ryle.

“I’ve heard people say, ‘Why wouldn’t you just leave? Why would she stay?’” Baldoni told Variety magazine last month. “We know that abuse happens to women of all ages. But it also happens to powerful women. It happens to very strong women. It happens to affluent women.”

Domestic violence resources: How you can get help

If you are a victim of domestic violence, The National Domestic Violence Hotline allows you to speak confidentially with trained advocates online or by the phone, which they recommend for those who think their online activity is being monitored by their abuser (800-799-7233). They can help survivors develop a plan to achieve safety for themselves and their children.

Safe Horizon's hotline offers crisis counseling, safety planning, and assistance finding shelters 1(800) 621-HOPE (4673). It also has a chat feature where you can reach out for help from a computer or phone confidentially. 

Survivors can also call the New York City Anti-Violence Project's 24/7 English/Spanish hotline at 212-714-1141 and get support. If calling is not safe but email is possible, make a report at avp.org/get-help and leave safe contact information, and someone will reach out.