Zack Snyder never really believed that his cut of “Justice League” would see the light of day. It has technically existed since January 2017, but it wasn’t in any shape to be released. It was four hours, in black and white, had storyboards where visual effects were supposed to go and an unfinished score.

“When I finished it, I said, oh well, no one will ever see this movie,” he said.

Although he’s officially credited as the director of the DC superhero mashup with Gal Gadot’s Wonder Woman, Ben Affleck’s Batman and Jason Momoa’s Aquaman that hit theaters in the summer of 2017, he and Deborah Snyder — his wife and producing partner — had stepped away from the film months earlier. Relations had strained with the studio, and the pressure was getting to be too much, especially after the suicide of their 20-year-old daughter Autumn. So the Snyders walked away, and Joss Whedon was hired to revamp and finish “Justice League.” The result was both a critical and financial letdown, and, according to cast members like Ray Fisher, who plays Cyborg, a toxic environment too.

The Snyders had mostly disconnected from the whole ordeal, but fans wouldn’t stop asking for The Snyder Cut. And their gestures kept getting more and more elaborate: Planes with #ReleasetheSnyderCut banners were flown over the Warner Bros. lot in Burbank and during the 2019 San Diego Comic-Con. They even leased a billboard in Time’s Square. Over the years, the hashtag became so ubiquitous, it even turned into a bit of a joke. Why on earth would a studio pay for a redo of an epic disaster?

Well, a few things happened: There was a change of leadership at the studio and suddenly everyone was in search of content for their new streaming service HBO Max. Warner Bros. Pictures Group chair Toby Emmerich asked the Snyders if they could release what they had.

“We were like, it’s really rough,” Deborah Snyder said. But they saw an opportunity to finish what they started, and she got to work putting together a pitch. It was somewhat familiar territory for the former advertising executive but also in many ways entirely unprecedented.

“I think the biggest challenge was to convince HBO Max that it was worth the money to do it…at the end of the day, for them, it’s a business deal. And they if they’re going to spend X, they want to make sure they’re getting a return on that business,” she said. “And with a movie that had already come out we needed to also show everyone that this was a different animal. This wasn’t the same thing.”

The fans were a crucial component. For HBO Max, it meant possible subscriptions. And the Snyders got the go-ahead to finish the score, add some 2,650 visual effects and film an additional scene with Jared Leto’s Joker. It even proved beneficial that everything shut down because of COVID: It freed up the visual effects houses that are usually booked up years in advance.

The result, “Zack Snyder’s Justice League,” debuts on HBO Max on Thursday. It’s not just a director’s cut. It’s a whole new movie. And, it seems, even critics have gotten on board. As of Wednesday, it was sitting at 78% on Rotten Tomatoes — a vast improvement over the original’s 40%.

“It’s the journey of the team coming together. To be able to explore each member of that team and who they are and what their struggles are in this format? We wouldn’t have been able to do that (for theaters),” Deborah Snyder said. “Now we really get this really immersive journey that we get to go on with the characters. And I think at the end it’s more fulfilling. We care about them more because you see where they’ve come from.”

Deborah Snyder said that it “still doesn’t feel super real.” It’s mere weeks since they’ve finished it. And it’s also the closing of a chapter. Although the Snyders were some of the main architects of the modern DC universe going back to 2013’s “Man of Steel” and behind the casting of people like Gadot and Momoa, they are moving on to different things, like Netflix’s “Army of the Dead,” which comes out in May. And the DC world is going on without them.

The Snyders remain immensely grateful for the fans, but not just because of their passion for getting the Snyder Cut released. After their daughter’s death, they decided to be public about the fact that it was suicide and to support the American Foundation for Suicide Prevention (ASFP).

“We felt like we were public enough that we could make a statement. A lot of times with mental health, there’s such a stigma and people are afraid to talk about it or embarrassed,” she said. “Through that journey with Autumn, we very many times felt the same way.”

What they didn’t ever expect was that the fans would also jump on that cause. In the end, fans contributed some $500,000 to the ASFP.

“That I think touched us more than anything else,” she said. “At the end of the day, you know, ‘Justice League’ is a movie. It means a lot. And the characters mean a lot to a lot of people. But actually helping people…especially people that are struggling? To me, that means so much more.”