In a recent interview, Singer—who's busy filming next year's X-Men: Apocalypse—revealed that there's been initial talks of a live-action X-Men and Fantastic Four crossover.
"Those ideas are in play," he says. "That would be a natural match-up because they're both ensemble films and there is a natural mechanism by which to do it."
And what might that "natural mechanism" (using the term "natural liberally, given that it's a comic boo universe) be? Why, time travel, of course!
"It deals with time," Singer revealed in an interview with Yahoo Movies. "That's all I'm going to say."
Obviously, it wouldn't be Singer's first rodeo with time-travel. He first played hop-scotch with the time stream in 2014's X-Men: Days of Future Past, bending all sorts of continuity rules along the way. So, there's no reason why he coulndn't do the same to get the current X-Men cast--who are currently in the eighties--in sync with Trank's modern-day Fantastic Four. While Singer digressed that Fox will wait to see how August's Fantastic Four, and it's already-slated sequel, will perform before greenlighting such a crossover, it's clear that Fox is getting its (superpowered )ducks in a row should the box office numbers go their way.
To see when Fantastic Four, X-Men: Apocalypse and Fox's other Marvel movies hit theaters, head to ComicBook.com's comic book movie database.