The newly released Flash movie has been in development for…quite a long time, having survived several regime changes that hit the DCEU and Warner Bros. overall. It was decided around 2017 that the film would effectively function as a swan song for the DCEU movies, so its general endpoint was always going to be as a refresh for whoever ended up taking control of the films down the line. But even the final film as it’s currently in theaters had a few different permutations to its ending, up to and including one of its final big cameos.

Spoilers for The Flash from this point onward.

After saving the multiverse from the mess he created, Barry Allen shows up at a courthouse for his father’s hearing and meets up with Bruce Wayne. But instead of Ben Affleck, the Bruce he meets is actually George Clooney, who previously played the character back in 1997’s Batman & Robin. According to the Hollywood Reporter, this ending wasn’t the only version shot—in fact, it’s the third version of the movie’s conclusion, and one that only took shape back in January.

After a pair of screenings, the decision was made to deliver a fake out after Barry thought he’d fixed everything. Having already gotten Keaton back for the main Batman, the filmmakers basically went, “How many Batmen can we get?” Thus, James Gunn and Peter Safran decided to try and get Clooney onboard. After watching a mostly finished cut of The Flash, the actor agreed, and the cameo was quickly shot in half a day on the Warner lot. WB managed to keep it secret by not screen testing it at all, and stopping just short of the actual reveal when the movie played at CinemaCon back in April. Press who attended screenings in early June were the first batch of people who saw the Clooney cameo, followed by its red carpet premiere days before the film’s release.

As for those other two endings, they basically went something like this. In its original version, Barry would’ve met with Keaton’s Batman and Supergirl (Sasha Calle) at the courthouse, indicating that he hadn’t reset the timeline quite like he thought he had. This would’ve reversed their deaths from earlier in the film, and it was the ending that had been screen tested several times. In the second version, Supergirl would’ve been joined by Henry Cavill’s Superman and Gal Gadot’s Wonder Woman (the latter appeared earlier in the movie), while Keaton remained as Batman. In Supergirl’s case, this would’ve left open the door for Calle to return (since her solo film had already been junked), since the producers didn’t want audiences’ last memory of the character to be her getting killed by General Zod.

Both of those endings, though, were prior to Gunn and Safran getting brought on to run DC Studios. When those two took over and other plans were made for DC movies, that resulted in the ending that’s currently playing in theaters. As one insider reportedly told THR, “It’s rare that you have a movie in post-production that faces three separate regimes with three separate agendas. None of them were scrapped because of ill will, just different visions.”

That’s quite a lot to lock down an official end for one movie, not helped by the fact that it had multiple people dictating what and who it was allowed to feature. Maybe those two alternate versions will show up in special features for the home release?

The Flash is now playing in theaters.

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