We know that the principal cast of X-Men: First Class will be back, which mainly includes Michael Fassbender, James McAvoy, Jennifer Lawrence, Nicholas Hoult, and January Jones. We also know that Patrick Stewart and Ian McKellen will be returning, along with a number from the original X-Men cast.
So apart from those actors, who else will be returning to the X-Men world once again with Days of Future Past? We will definitely see Hugh Jackman, and he has hinted that you’re likely going to see most of the original cast back for this film, including Halle Berry, James Marsden, Famke Janssen, and Anna Paquin. According to Moviehole, Jackman added, “You wouldn’t have enough room on the page after you’ve listed them all. Every other actor who’s ever put on a superhero uniform will be in it.”
Caleb Landry Jones, who played a crucial part in the first movie as Banshee spoke about returning, saying that he was unsure and adding, “I love Banshee, I enjoy playing him. If they ask me to do another one, I'm excited to dive a little further and show a little more of who he is." Rose Byrne is also not confirmed as returning, but when asked about the sequel and whether she would like to return, she said, “Yeah, of course, absolutely!" Famke Janssen also weighed in on the possibility of Jean Grey returning to the franchise, telling MTV, “I'm waiting by the phone. It would be very surreal. I would be honoured to be a part of any of these X-Men movies. It would be great. [But] she died as Jean Grey and she died as the Phoenix. Is there another incarnation of her that we haven't seen? I don't think so. Bryan Singer is a very smart guy, but if we go younger, I'm out too. I'm all for an interpretation of that on whatever front. I'd be thrilled."
X-Men: Days of Future Past is set to come out in 2014.