X-Men: First Class writer-director Matthew Vaughn helped pen the script for Days of Future Past, but he didn't originally envision it as the followup to First Class. Speaking to Uproxx, he revealed that he had planned a young Wolverine movie that would have been released after First Class and set up the events of Days of Future Past.

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"The reason I haven’t done sequels in the past is they just weren’t exciting me. And on Days of Future Past, even though I co-wrote the bloody thing, the reason I bailed out of it is two things: First, I respect Bryan Singer hugely and X-Men is Bryan’s world and I feel he let me play in his sandbox. I enjoyed it, but it wasn’t my sandbox. I wanted my own sandbox. And, second, I didn’t want to do Days of Future Past next. I felt that one should be in a trilogy and Days of Future Past should be the finale of that story," he explained. "I would have done a film in-between where you meet the young Wolverine and a new character, and then in Days of Future Past became the young Wolverine and the old Wolverine and just really blow it out."

Though Vaughn ultimately left Days of Future Past, he went on to helm another successful comic book adaptation: Kingsman: The Secret Service, which has a sequel due out on September 22.

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Bryan Singer ushered Marvel's merry mutants onto film with 2000's X-Men. He proceeded to direct X2, Days of Future Past and Apocalypse, helming four out of the franchise's six films. Vaughn's First Class was an outlier like The Last Stand, which was directed by Brett Ratner, though Vaughn's film earned critical praise where The Last Stand was widely panned. Dark Phoenix, the next installment in the franchise, will be helmed by longtime X-Men producer Simon Kinberg; this will be Kinberg's first directing credit.

Opening November 2, 2018, X-Men: Dark Phoenix -- the next installment in the X-Men franchise -- stars James McAvoy as Charles Xavier, Michael Fassbender as Magneto, Jennifer Lawrence as Mystique, Nicholas Hoult as Beast, Sophie Turner as Jean Grey, Alexandra Ship as Storm, Tye Sheridan as Cyclops and Kodi Smit-McPhee as Nightcrawler.

via ScreenRant