The complicated friendship and rivalry between Charles Xavier and Erik Lehnsherr, aka Magneto, has formed the heart of Fox's X-Men franchise for the past 17 years. They're mirrors of one another, reflecting two sides of a philosophical debate about humanity and mutantkind that frequently erupts into physical conflict. Yet, after battles, imprisonment and even death, their relationship endures.

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However, as the studio moves beyond the acclaimed "Logan" and the widely criticized "X-Men: Apocalypse," it will move away from that series-defining friendship.

“We cannot, once again, explore the Erik/Charles dynamic,” longtime franchise producer Lauren Shuller Donner told Vanity Fair, adding that the new approach is “both liberating and makes me nervous — it’s mostly liberating." While the two character remain "essential" to the world of the X-Men, she conceded, “there are other stories to tell.”

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Patrick Stewart and Ian McKellen originated the roles of Professor Xavier and Magneto, respectively, in 2000's "X-Men," where they were portrayed as old friends who parted ways over a disagreement about whether mutants can peacefully coexist with humans. That philosophical split played out in the sequels "X2" and "X-Men: The Last Stand," while the roots of their friendship and conflict were explored in the prequels "X-Men: First Class," "X-Men: Days of Future Past" and "X-Men: Apocalypse," where their younger versions were portrayed by James McAvoy and Michael Fassbender.

Now, it seems, the X-Men are ready to move beyond that.

"Logan," Hugh Jackman's farewell to Wolverine, is in theaters now. Josh Boone's "X-Men: The New Mutants" is expected to begin filming in April in Montreal, followed in May by the reported "soft reboot" of the X-Men series, tentatively titled "X-Men: Supernova."