20th Century Fox has registered "Days of Future Past" with the MPAA.

After announcing its 2013-2014 release slate including a July 18, 2014 release for the untitled "X-Men: First Class" sequel, 20th Century Fox has apparently registered an X-Men related film title with the MPAA Title Registration Bureau. As discovered by Ain't it Cool News, the studio has registered "Days of Future Past," a possible indication that Vaughn's next film will deal with time travel and alternate futures.

The original "Days of Future Past," written by Chris Claremont with art by John Byrne, alternated between the present-day X-Men fighting to stop the Brotherhood of Evil Mutants' assassination attempt on Senator Robert Kelly and a dystopian future where Sentinels rule the United States, mutants live in internment camps and most of the super-powered beings of the Earth have been killed. Rachel Summers sends the psyche of the future Kitty Pryde into the body of her younger self to warn the X-Men about the future and stop the assassination.

While it is currently unknown whether the "Days of Future Past" registration relates directly to Matthew Vaughn's untitled "First Class" sequel, it would be an excellent way to explore possible directions for the franchise's future and allow for an in-continuity reboot of the X-Men films. Either way, a big screen adaptation for one of the most popular X-Men stories of all time could be in the cards -- it's just a question of when and where more details will surface.

Stay tuned to CBR News for more on "X-Men: First Class 2."