Truth About Blake Lively's Feud With 'This Is Us' Co-Star Justin Baldoni Laid Bare: 'It’s Her Name and Career on the Line'

It should have been a huge win.

In its opening weekend, It Ends With Us — the film adaptation of Colleen Hoover's bestselling 2016 novel that debuted in theaters on August 9 — earned a jaw-dropping $50million domestically and $80million worldwide against a $25million budget, exceeding all expectations.

News of such an epic success for the project, its movie studio, Sony, and the film's star and producers, Blake Lively and Justin Baldoni, who also directed, should have dominated headlines.

But instead of basking in the great press, the movie's main players and their camps have been doing damage control.

Whispers of a feud between the costars have been growing for weeks. First, the two raised eyebrows by failing to promote the movie about an abusive relationship together, attending different screenings and events.

Then rumors of on — and off — set drama exploded when sleuthing fans noted that Blake and Colleen had unfollowed Justin on Instagram — and that none of the main cast were following him.

The distracting scandal went mainstream when the pair didn't pose together for a single shot at the Aug. 6 premiere, where costars like comedian Jenny Slate as well as the book's author curiously danced around questions about Justin in red carpet interviews.

Since then, "it's become a real war of worlds", an insider tells RadarOnline.com. "Fingers are being pointed from both camps with all kinds of nasty accusations being thrown around."

From the start, Blake, an executive producer of the flick, seemed to be undercutting Justin's role as a director, telling E! News that she called in her husband, Ryan Reynolds, to rewrite the dialogue for "the iconic rooftop scene".

That was news to the film's screenwriter, Christy Hall, who said she'd believed it had been improvised.

After footage surfaced of her and Justin having a heated conversation on set, a report appeared that he had "fat-shamed" the 37-year-old, who'd recently given birth to her fourth child, humiliating her by asking about her weight before a scene in which he had to lift her.

The narrative — that he was controlling and possibly dangerous — was furthered by her Aug. 10 comments to Digital Spy that "it's critical to have an intimacy coordinator... for everyone's safety".

Things looked so bad for Justin that he hired a crisis PR manager — the same one who represented Johnny Depp during the actor's defamation trial with ex-wife Amber Heard.

Positive headlines soon emerged, including one about how Justin's production company, Wayfarer Studios, was partnering with a domestic violence support organization to provide resources and information to abuse survivors.

Stories defending the dad of two also made the rounds, with one insisting he was "actually viewed quite favorably by a lot of the crew, as he was generally a nice guy to work with".

Despite the appearance that the main cast has sided with Blake, others on set "feel like Justin got screwed".

Indeed, a source said the Jane the Virgin star was not, in fact, body-shaming his leading lady, pointing out that Justin and Blake had the same on-set trainer.

Continuing, they added it would have been surprising that Blake would have considered talk about a physical scene inappropriate, considering the actor-director has back problems and had recently undergone treatment for a disc injury before being hospitalized in June for a related infection.

However, Justin has publicly praised the Gossip Girl alum, calling her a "powerhouse."

"She is a dynamic creative. She had her hands in every part of this production, and everything she touched she made better." He's also acknowledged the movie wasn't smooth sailing, telling Elle UK, "There's always friction that happens when you make a movie like this. Then, at the end of the day, it's that friction, I believe, that creates the beautiful art. Everything in life needs friction to grow."

Yet the tide began turning against Blake. She faced intense backlash on social media, where users branded her a "mean girl", "fake" and "a villain" as they dissected the feud drama.

Amid praise for Justin for discussing the movie's serious themes, like intimate partner violence, Blake was accused of using the movie's media events to boost her own brands.

"Grab your friends, wear your florals, and head out to see it," the actress said in a promo for the movie on Instagram. One commenter on X summed up the disconnect, writing, "Blake Lively spending the entire press run for her new film, which is about domestic violence and abuse, acting like it's a fun gals night... and promoting her businesses at the same time is INSANE behavior."

Past troubling conduct also resurfaced. On Aug. 11, reporter Kjersti Flaa posted a clip on YouTube titled "The Blake interview that made me want to quit my job".

In the sit-down for the 2016 film Café Society, Blake mocked the LA-based Norwegian journalist for congratulating her on her "little bump".

Noting Blake had recently announced her second pregnancy outside of the interview, the actress then chided the reporter for inquiring about the movie's beautiful period costumes.

Blake wondered if Kjersti would "ask the men about the clothes". Taken aback, the reporter insisted that she would.

The pushback put the actress on the defensive. Reframing her "girls' night" attitude, she said of her character, "She's not just a survivor, and she's not just a victim, and while those are huge things to be, they are not her identity."

What it may all boil down to is control.

A source says Blake and Ryan, hoping to seal their picture-perfect image as Hollywood's power couple, stealthily took over the film.

In addition to rewriting scenes, Blake reportedly hired her own editor to make an alternate cut of It Ends With Us. The editor was allegedly the same one who crafted Ryan's summer blockbuster, Deadpool & Wolverine.

An insider explained: "She had a vision for how this story should be told and wanted to put out the best movie possible."

They speculated that, had the movie performed poorly, Blake "would have downplayed her creative contributions".

The next fight may be over the sequel. Justin's production company owns the films right to the next book in the series, It Starts With Us.

However, the insider said the sequel is "the last thing on his mind right now".

"Maybe he'll sit on the project for years and refuse to sell and make Blake suffer. Certainly, she and Ryan would scoop up the rights in a minute if they were available."

Amid the chaos, one thing is clear. Our source said: "There are two sides to this. And it's highly unlikely these two will ever work together again."

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