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Now it's starting to get exciting… Both Ian McKellen and Patrick Stewart are returning to the X-Men franchise in their signature roles for the upcoming X-Men: Days of Future Past, according to a tweet by director Bryan Singer.

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The director of 2000's X-Men and 2003's X2 tweeted today, "Thrilled to announce @ianmckellen118 & @SirPatStew are joining the cast of #XMEN #DaysOfFuturePast #magneto #professorX More to come…"

It's clear now that we'll see both the younger and older versions of Magneto and Professor X in the new film -- said to be inspired by an Uncanny X-Men comic book storyline that ran back in 1981 – which contains a complicated time-travel storyline and alternate future scenario that bridges the gap between mutants of the past and mutants of the future.

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Singer took on directing responsibilities for the follow-up to X-Men: First Class after Matthew Vaughn departed the project.

X-Men: Days of Future Past is expected to arrive in theaters on July 18, 2014.