At one time, 20th Century Fox was planning a major crossover between its Marvel Comics film properties that would have pitted the X-Men and Fantastic Four against each other in brutal combat, a la Marvel's Civil War, according to The Hollywood Reporter.
Citing a "secret source," THR reports that Fox hired X-Men: First Class screenwriters Edward Miller and Zack Stentz in 2010 to write the crossover film, which would purportedly have kicked off with a massive explosion caused by Johnny Storm taking on Molecule Man in New York.
Per the trade's "secret source," the X-Men would have responded to the incident, leading the teams to take sides and fight. The big battle would have reportedly culminated in Mr. Fantastic turning his arms into super thin, razor sharp scissors and cutting off Wolverine's arm's. After that, the teams would have settled their differences in preparation for a team-up movie where they fight off a Skrull invasion.
Stentz confirmed the script's existence earlier this month, going so far as to include Daredevil (whose film rights still belonged to Fox in 2010) in the action, and name Paul Greengrass as a director who looked at the script.
"My ex-partner and I, when we were working at Fox and working on X-Men: First Class, we did a secret movie for them that, I can't tell you what the plot was, but I can tell you that it used all of the characters, all of the Marvel characters that Fox had at the time in 2011," Stentz told CinemaBlend. "It used the X-Men. It used the Fantastic Four. It used Daredevil. It used Deadpool. Daredevil was still at Fox at the time. And it was a really cool freakin’ script. We almost had Paul Greengrass directing it, which would've been so cool, but he had another project to do instead. It didn't end up going, but it was a script I was really proud of and it would've been really good."
Of course, no such movie took place and both the X-Men and Fantastic Four franchises were rebooted - X-Men in 2011 with X-Men: First Class which produced three sequels (including this month's Dark Phoenix), and Fantastic Four with an eponymous reboot in 2015 which fizzled for critics and fans alike. And of course, Skrulls were key characters in Marvel Studios' Captain Marvel.
Both franchises now stand to undergo another reboot as the film rights to the X-Men and Fantastic Four are in the hands of Marvel Studios thanks to parent company Disney's purchase of 20th Century Fox.