Two long-running casting rumors were confirmed Thursday with news that Maisie Williams and Anya Taylor-Joy will play Wolfsbane and Magik in Fox's X-Men spinoff New Mutants. But at the same time, two others were shot down.

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Borys Kit, who wrote The Hollywood Reporter's story about Williams and Taylor-Joy, tweeted that James McAvoy won't reprise his franchise role as Professor Charles Xavier , as had been rumored since at least January. Likewise, actor Nat Wolff apparently won't reunite with his The Fault In Our Stars director Josh Boone in the role of Cannonball, as had been speculated.

On NEW MUTANTS: other rumored castings - James McAvoy as Prof X - not true. He is not in movie, per sources.— Borys Kit (@Borys_Kit) May 11, 2017

On #NewMutants: other rumored casting - Nat Wolff as Canonball - not happening either.— Borys Kit (@Borys_Kit) May 11, 2017

Although McAvoy's involvement in New Mutants would've provided a tangible link to the larger X-Men franchise, Xavier is only a peripheral figure in "The Demon Bear Saga," the influential 1984 Marvel Comics storyline on which the film is based. In that arc, by Chris Claremont and Bill Sienkiewicz, the teenage students of Xavier's School For Gifted Youngsters are isolated from the world, and their mentors, by a freak snowstorm, and must band together to save their teammate Danielle Moonstar, and themselves, from the enormous demonic bear that killed her parents.

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In addition to Wolfsbane, Magik and Danielle Moonstar, the film is expected to feature classic New Mutants characters Cannonball, Sunspot and Warlock. New Mutants is targeted to begin this summer in Montreal for release on April 13, 2018.