<P> Additionally, Famke Janssen and James Marsden reprise their roles as Jean Grey and Scott Summers / Cyclops respectively in cameo appearances . Lucas Till reprises his role as Alex Summers / Havok . Evan Jonigkeit portrays Mortimer Toynbee / Toad . Gregg Lowe portrays Eric Gitter / Ink . X-Men comic - book writers Len Wein and Chris Claremont appear as United States congressmen . Michael Lerner plays Senator Brickman . Mark Camacho portrays U.S. President Richard Nixon . Singer cameos as a man with a small film camera as Magneto walks away after Mystique's escape in Paris . In a post-credits scene, Brendan Pedder portrays the ancient mutant, En Sabah Nur . </P> <P> Producer Lauren Shuler Donner stated in August 2006 that a continuation of the X-Men main film series would require a renegotiation . New cast members of X-Men: The Last Stand were signed, while the older cast members were not . Donner said, "There is forty years worth of stories . I've always wanted to do' Days of Future Past' and there are just really a lot of stories yet to be told". She later pitched the idea of a fourth installment of the X-Men franchise to director Bryan Singer, following the completion of the 2011 prequel X-Men: First Class . In March 2011, Donner said the film was in "active development at Fox"; she said, "We took the treatment to Fox and they love it...And X4 leads into X5". </P> <P> 20th Century Fox saw X-Men: First Class as the first film of a new X-Men trilogy . Donner compared the franchise plans to the darker, more mature content of the Harry Potter film series . Early reports said Matthew Vaughn and Singer were returning to direct and produce the sequel, respectively . While still attached to the project as a director, Vaughn said, "First Class is similar to Batman Begins, where you have the fun of introducing the characters and getting to know them, but that takes time . But with the second one, you can just get on with it and have a rollicking good time . That's the main difference between Batman Begins and The Dark Knight". Describing the possible beginning of the film, Vaughn said, "I thought it would be fun to open with the Kennedy assassination, and we reveal that the magic bullet was controlled by Magneto". Singer said the film could be set around the civil rights movement or the Vietnam War, and that Wolverine could once again be featured . Singer also talked about "changing history" in an interview with Empire magazine . He said he does not want people to panic about events in the past "erasing" the storylines of the previous X-Men films, as he believes in multiverses, explaining the possibility of certain events can exist equally in the histories of alternate universes . </P> <P> Kinberg said the main focus of this film was the future of the X-Men film series . With the use of cast members from the original trilogy and from First Class, they needed to decide the sequels' destination . In preparation for the film, Kinberg studied films about time travel, including Back to the Future, The Terminator, and Terminator 2: Judgment Day . Singer originated a philosophy and a set of rules for the time travel in the film so the story would be as plausible as possible . </P>

Marvel characters in x-men days of future past