Marvel Studios has had an amazing success this summer with their superhero crossover film 'The Avengers' and it would only make sense to try and repeat that trend. Now we have some hints that two familiar groups of superheroes might be combining for an upcoming sequel...

"Days of Future Past." It might not mean much to everyone but for big comic nerds (ahem...), it's one of the finest storylines Marvel has ever told. Told in the 'Uncanny X-Men' series in the early-80s, the series takes place in an alternate future where mutants are kept in internment camps and transfer back in time to help prevent the assassination of a senator that led to rabid anti-mutant hysteria. It's big and bold and occasionally confusing but it's brilliant and could be the plot of the next 'X-Men' movie.

Ain't It Cool News has unearthed news that Fox, who owns the rights to the 'X-Men' movies has registered the title 'Days of Future Past' with the MPAA, which studios do when they're planning an upcoming movie (it prevents another studio from moving forward with a film of the same title).

And this is all speculation here but the news opens up the possibility that the upcoming 'X-Men: First Class' sequel could actually be a crossover with Bryan Singer's original 'X-Men' films.

It would allow for some mutant cameos in the present day timeline but primarily a leading role for Wolverine (Hugh Jackman). As the film travels back in time, it could then include the 'First Class' cast, essentially serving as a crossover between the original 'X-Men' films and the rebooted universe. The storyline also heavily features Mystique (good for Jennifer Lawrence), which would put two of the biggest actors on screen together. (Also, coincidentally, the storyline takes place in 2013.)

It's a crazy idea and may not be what Fox has in mind, but it's certainly a strong possibility given how 'Avengers' has performed (and would allow Fox to essentially make two X-Men sequels in one).

What do you think? For more information on 'Days of Future Past' you can read up on the Wikipedia page here.