Anya Taylor-Joy and Maisie Williams have officially boarded Fox's upcoming X-Men spin-off, New Mutants.

The duo have long been rumored to be involved with the project, with concept art even showing Williams as Wolfsbane being released by the film's director, Josh Boone, earlier this year. However, according to Hollywood Reporter, Boone was unable to secure the actresses for the project -- until now.

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Boone added a second confirmation to the news of Taylor-Joy and Williams' involvement with an Instagram post earlier today, in which he simply posted a screenshot of the Hollywood Reporter's article.

As previously rumored, Taylor-Joy has been cast as Magik, while Williams will play Wolfsbane. Other characters set to round out the New Warriors roster include the Native American Danielle Moonstar, Brazilian ladies man Sunspot and a Kentuckian code-named Cannonball. According to the Hollywood Reporter, Warlock, the alien being of technological origins, is also slated to appear in the film.

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With such a diverse lineup of characters, the studio is reportedly keen on finding ethnically appropriate actors for the roles. The project, which will be filming under the name Growing Pains, is set to enter production in July.

The film will be written and directed by Josh Boone, who is perhaps best known for directing The Fault in Our Stars. New Mutants is currently set to hit theaters on April 13, 2018.