Fox's eagerly awaited X-Men spinoff The New Mutants will eschew the traditional trappings of superhero movies and instead embrace the horror genre.

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"We are making a full-fledged horror movie set within the X-Men universe,” director Josh Boone told Entertainment Weekly. “There are no costumes. There are no supervillains. We’re trying to do something very, very different.”

The turn toward horror shouldn't come as a major surprise to those familiar with the film's rumored inspiration, the seminal 1984 Marvel Comics storyline "The Demon Bear Saga," by Chris Claremont and Bill Sienkiewicz. The arc, which unfolded in The New Mutants #18-20, found the teenage students of Charles Xavier’s School for Gifted Youngsters isolated from their mentors and the world by a freak snowstorm and forced to overcome their own differences to save themselves and their teammate Danielle Moonstar from a demonic bear that killed her parents.

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After more than a year of rumors, Boone earlier this month cast Game of Thrones star Maisie Williams as Wolfsbane and Atlantis actress Anya Taylor-Joy as Magik. Citing "sources close to the production," EW adds that 13 Reasons Why actor Henry Zaga will soon be announced as Sunspot, and that fan favorite Rosario Dawson may also be in talks for a role.

EW adds another wrinkle that both signals a significant departure from the source material and help to explain why James McAvoy won't have a cameo as Professor Xavier. The site's source offers a broad overview of the plot: “Held in a secret facility against their will, five new mutants have to battle the dangers of their powers, as well as the sins of their past. They aren’t out to save the world — they’re just trying to save themselves.”

Arriving in theaters on April 13, 2018, The New Mutants is expected to begin production in July.