In the days leading up to its 2017 release, Zack Snyder was busy filming Justice League. Then he had to withdraw from the work due to a personal tragedy, and Warner Bros. brought on Joss Whedon to radically alter the movie. Much of what Snyder had filmed was removed from the project, until three years of the #RestoretheSnyderCut movement finally prompted the studio to finish Zack Snyder's Justice League according to the director's personal vision for an HBO Max release.

The VFX supervisor for Zack Snyder's Justice League, Bryan Hirota, recently revealed to CBR how the complicated history of the "Snyder Cut" necessitated a month of prep work before the VFX team could even begin to add CGI to the film.

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"There was a surprising amount of forensic work that had to go into the project. We needed to figure out exactly what was archived, what still worked as expected since technology had moved on, what was missing and numerous other questions like that. We spent a month just bringing the show back online and sorting through, asking/answering questions and prepping the material before we were at a place where we could launch into the work full force. The process of chasing down and vetting details to make sure the work that needed to change between the two cuts was actually changed -- and, likewise, to undo changes -- continued throughout until the end."

For the longest time, Warner had insisted that the "Snyder Cut" did not exist, while fans in turn insisted the Cut was real. The truth turned out to be somewhere in between. There was certainly footage that Snyder had filmed for his cut of Justice League, but the footage was missing the crucial CGI elements that the VFX team spent all of last year incorporating into the movie to give it a finished look. According to Hirota, there is one particular scene his team pulled off for Zack Snyder's Justice League that is a personal favorite, involving Barry Allen aka Flash turning back time.

"I'm proud of all the work we completed for the film, but if I had to pick a moment to spotlight it would be the "cosmic rewind" moment after the Motherboxes achieve unity and destroyed the league. Seeing Barry phase through the destruction and break the rules to turn back time was something that I was quite pleased with visually, and I hope it's something people find pleasing in terms of aesthetics. I also think it's a nice beat narratively and helps complete Barry's arc through the film."

Zack Snyder's Justice League stars Ben Affleck as Batman, Gal Gadot as Wonder Woman, Henry Cavill as Superman, Amy Adams as Lois Lane, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, Jeremy Irons as Alfred Pennyworth, Diane Lane as Martha Kent, Ray Porter as Darkseid, Ciarán Hinds as Steppenwolf, Jesse Eisenberg as Lex Luthor and J.K. Simmons as Commissioner Gordon. The film is currently available on HBO Max. This news originated at CBR.