The cast of Fox's "X-Men" spin-off film "The New Mutants" has been announced.

The Hollywood Reporter reveals that both "Game of Thrones" star Maisie Williams and "The Witch" actress Anya Taylor-Joy will be part of the highly anticipated spin-off film that will be helmed by "The Fault in Our Stars" director Josh Boone.

According to the report, Williams will portray the role of Wolfbane, a girl who is having a hard time merging her religious beliefs with her ability to transform into a wolf. On the other hand, Taylor-Joy will take on the role of a girl named Magik, who discovers the power of sorcery and utilizes transportation discs to go from places to places. Magik is also described as the sister of Colossus, a mutant who also appeared in "Deadpool."

The report also reveals that Boone has been thinking about getting both actresses since last year, but only managed to make an offer to them after the movie was given the go signal early this year.

Other characters who will be included in the film include other young superheroes named Moonstar, Sunspot, Warlock, and Cannonball. But Fox has yet to discover the right actors to play the roles, particularly a South American actor for Sunspot and a Native American actor for Moonstar.

Boone will co-write the film's script together with Knate Gwaltney. It will be co-produced by Simon Kinberg, who told Deadline in 2015 that they are excited for the film. "We're so excited to explore this part of the X-Men universe, and so excited to do it with Josh, who is uniquely suited to tell this story about young characters."

Reports claim that production for "The New Mutants" will begin sometime in July, while the film is slated for release in April 13, 2018.

More cast members are expected to be announced before filming starts.