Although this is just a rumor at this point, it looks like another actor from a previous X-MEN movie will return for X-MEN: DAYS OF FUTURE PAST. The actor appeared in X-MEN: THE LAST STAND, and according to Showbiz Spy, filmed a "secret cameo" for Bryan Singer's new movie. Some fans might want to be surprised by his appearance in X-MEN: THE LAST STAND, so I do consider this to be a spoiler. If you want to know which actor I'm talking about, I'll meet you after the spoiler buffer.
So which actor might have a cameo in X-MEN: DAYS OF FUTURE PAST? A source for Showbiz Spy has told the site Kelsey Grammer will return as the future version of Beast in the upcoming movie. Their source says Grammer shot his scenes during post production "on the Fox lot under the impression that Kelsey would be on set to film a pilot for a different project." The insider also says, “It wasn’t hard to get him to sign on for a guest appearance. He jumped at the opportunity the second it was brought to his attention."
Kelsey Grammer was excellent as Beast, but in my opinion he was criminally underused in X-MEN: THE LAST STAND. It makes sense to have Grammer return as future Beast, even if it is only a cameo. But like I said though, this is only a rumor, and we'll probably have to wait until the new film hits theaters before we know if it is true or not.
X-MEN: DAYS OF FUTURE PAST also stars Hugh Jackman, Michael Fassbender, Jennifer Lawrence, Patrick Stewart, Ian McKellen, Nicholas Hoult, Peter Dinklage, Ellen Page and Shawn Ashmore, and will be released on May 23rd, 2014.