Tim Burton brought the Dark Knight back to the big screen in 1989's Batman and later delivered a pitch-perfect sequel with Batman Returns. From there, he planned to do the same for the Man of Steel, casting Nicolas Cage in the ill-fated Superman Lives.
The project fell apart long before cameras could start rolling and Supes remained on the shelf until Superman Returns attempted to recapture the magic of Superman: The Movie (it didn't work and Zack Snyder later rebooted the hero in 2013's Man of Steel).
In the closing moments of The Flash earlier this summer, Cage finally got to suit up as Superman for a peculiar CG sequence which saw him do battle with Superman Lives' widely discussed giant spider. Michael Keaton, meanwhile, took on a supporting role as the older Bruce Wayne.
Talking about very nearly getting to direct Batman and Superman movies, Burton recently told the British Film Institute, "When you work that long on a project and it doesn’t happen, it affects you for the rest of your life. Because you get passionate about things, and each thing is an unknown journey, and [Superman Lives] wasn’t there yet. But it’s one of those experiences that never leaves you, a little bit."
"But also it goes into another AI thing, and this is why I think I’m over it with the studio," he continued. "They can take what you did, Batman or whatever, and culturally misappropriate it, or whatever you want to call it."
"Even though you’re a slave of Disney or Warner Brothers, they can do whatever they want. So in my latter years of life, I’m in quiet revolt against all this."
While he doesn't explicitly mention The Flash, Burton talking about Warner Bros. misappropriating his work probably tells you all you really need to know about how he felt to see his Superman transformed into a CG monstrosity (we're guessing he wasn't pleased with that Batman's story continuing without him either).
Warner Bros, originally planned for Keaton to continue playing the Caped Crusader in Batgirl, Aquaman and the Lost Kingdom, Batman Beyond, and Crisis on Infinite Earths. However, the formation of DC Studios has led to those plans being scrapped.
As for Burton, his superhero movie days are likely behind him and we're guessing that's not something he's too bothered about. We'll always wonder what might have been with Superman Lives but The Flash did at least give fans an idea!