Fox is building a unified X-Men movie universe with their next X-Men movie, Days of Future Past. There have also been rumors saying they want to have a cohesive universe for all their X-franchises as well as their Fantastic Four franchise—which can all crossover in the future too. What was once a rumor is now fact.
Confirmed by Fox creative consultant Mark Millar (via SFX), Fox's Marvel franchises will indeed be in one movie universe and crossover with each other, eventually.
“I don’t think it’s something anyone would want to rush into. Following that Marvel model, we want to establish things first. If you had a Fantastic Four relaunch, and Wolverine and the X-Men were in it, I think it would distract you from the Fantastic Four. You can make people aware that they’re existing in the same universe without making it a big crossover movie but it would be an injustice to the Fantastic Four not to make their first movie all about them.”
If Fox can do this right, then having two movie franchise teams partnered up together on the big screen could be a serious sight to see. That is if they can do it right, of course.
Right now, Fox is focused on prepping for X-Men: Days of Future Past, since it'll start shooting in April 2013 but do not doubt that there could be some kind of teaser leading into a Fantastic Four reboot.
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