It’s been 20 years since the world was introduced to Bryan Singer’s film, “X-Men.” And though it wasn’t the first (superhero films existed decades prior) and it wasn’t the most successful (Sam Raimi’sSpider-Man” would break records two years later), “X-Men” holds a significant place in the history of superhero films—proving they could be serious and meaningful in a post-“Batman & Robin” world and that they could be blockbusters once again. But getting to that point in 2000 took a lot of work and according to a new Observer report, there were a ton of really well-known people that came close to working on the film years before it actually hit the big screen.

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Back before David Hayter earned the screenwriting credit for Singer’s film, Fox had a number of other writers, many with huge projects under their belts, take a crack at the film. Those names include Andrew Kevin Walker (“Seven,” “Panic Room”), Christopher McQuarrie (“Mission: Impossible” films, “The Usual Suspects”), Ed Solomon (“Bill & Ted’s Excellent Adventure,” “Men in Black”), Tom DeSanto (“Transformers”), and Joss Whedon (“Avengers”). Eventually, it came down to Hayter who, compared to the previous writers who compiled drafts, was relatively new. Alas, it seemed to work out okay, huh?

But perhaps more shocking than the murderers’ row of writers that took a shot at “X-Men” are the actors that were seeking out roles and those that turned down roles to appear in the superhero film. We’ve always heard about names like Viggo Mortensen and Russell Crowe, who both turned down the role of Wolverine (let’s also not forget about the unfortunate situation with Dougray Scott…), but apparently Charlize Theron was offered the role of Jean Grey by Bryan Singer and David Hayter before she turned it down.

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And then you have the, uh, interesting choices of people that campaigned for roles but were clearly not considered serious options.

“I have lots of warm memories of people that came in wanting to be in the movie,” producer Ralph Winter revealed. “Michael Jackson was a big comic fan and wanted to play Charles Xavier. Shaquille O’Neal showed up at the offices and wanted to play Forge, who wasn’t in the movie.”

Hayter added, “Every day I was surprised by the faces coming in. Like, I’d find Mariah Carey sitting in my office wanting to go talk to Bryan about being Storm or something. So that’s always shocking.”

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Obviously, much like the current MCU, the actors that were eventually cast and appeared in “X-Men” and the various sequels and spin-offs have become iconic. And thankfully, the filmmakers and the studio never really considered Michael Jackson as Professor X. That would have been an unmitigated disaster of epic proportions. Like “Batman & Robin” multiplied by one million. So, even though “X-Men” has some issues in retrospect, it’s clear that the film could have been a lot worse and still is a significant piece of superhero film history and pop culture.