X-Men: Days of Future Past Director Teases "Marvel Mash-Up" Movie Follow-Up

Could we see elements 20th Century Fox's Fantastic Four franchise bleeding over into the X-Men movies after the release of X-Men: Days of Future Past? It doesn't seem entirely out of the question, after director Bryan Singer reportedly said he's considering a "Marvel Universe mash-up" movie to follow on the heels of the mutant-fueled time-travel adventure, which is set for release in 2014. Of course, the X-Men Universe is HUGE, and there's reportedly an X-Force movie already in development, with scripts for Magneto and Deadpool solo films that have been floating around for years. It's possible that "mash-up" could apply only in the sense that various disparate elements of the X-Universe will be seen onscreen together...but that seems to be a lot of what Days of Future Past is about.