Dan Stevens, Aubrey Plaza, Jean Smart Cast In ‘Legion’ X-Men Show For FX

Downton Abbey’s Dan Stevens, Parks and Recreation’s Aubrey Plaza, and Fargo actress Jean Smart have all just been cast in Legion — FX’s new and upcoming X-Men pilot, reports Us Weekly.

Dan Stevens, 33, has signed on to play David Haller in the pilot, written by Fargo creator Noah Hawley. Haller is the son of X-Men leader and founder Charles Xavier, a.k.a. Professor X, and is the son of Gabrielle Haller, an Israeli Holocaust survivor. David is struggling with mental health issues, having been in and out of psychiatric hospitals for several years, and is diagnosed as a schizophrenic before he begins to have feelings for a fellow psychiatric patient. Through this interaction, he realizes that the voices in his head may actually be real, and he may, in fact, be a Mutant.

Dan Stevens, Aubrey Plaza, Jean Smart Cast In 'Legion' X-Men Show For FX

Aubrey Plaza, 31, is playing the friend of Haller, Lenny, who has lived a life filled with drug and alcohol abuse but is ultimately optimistic about turning her life around. Jean Smart plays a therapist with unconventional methods named Melanie, according to the Hollywood Reporter. Whether or not their characters or Mutants or humans is not yet known.

Dan Stevens is probably most famous for his role as Matthew Crawley on Downton Abbey. His role on the period drama lasted three seasons before his character was killed off in a car accident. He has since made a transition into film acting, playing the role of Sir Lancelot in Night at the Museum: Secret of the Tomb in 2014. Stevens has also been cast as the Beast in the live-action adaption of Beauty and the Beast, opposite fellow-British actress Emma Watson.

Dan Stevens, Aubrey Plaza, Jean Smart Cast In 'Legion' X-Men Show For FX

The executive producers for the Legion X-Men spinoff show are Lauren Shuler Donner, Simon Kindberg and Bryan Singer (X-Men: Days of Future Past), and Marvel’s Jeph Loeb (Agents of S.H.I.E.L.D., Daredevil) and Jim Chory (Daredevil).

In anticipation for this comic book/television adaptation, fans can enjoy X-Men: Apocalypse starring James McAvoy, Michael Fassbender, Jennifer Lawrence, Oscar Isaac, and Nicholas Hoult, opening in theaters on May 27, 2016. The Legion pilot is going to begin production in March of this year, with no set premiere date announced.

Twentieth Century Fox seems to be expanding their X-Men universe by greenlighting this television pilot, in addition to giving the character of Deadpool his own movie later this month. It’s not yet known whether or not Legion will take place in the same continuity as the X-Men films, much like Agents of S.H.I.E.L.D. and Netflix’s Daredevil and Jessica Jones does with the Marvel Cinematic Universe.

“Legion has been in the works for a long time,” showrunner Hawley told TVInsider. “Some of that was Marvel dealmaking process. Fox has rights to make movies and sort of tacitly the rights to do TV, but they’ve never done it before so they had to work out all the details.”

“I think Lauren and Bryan had talked to Fox Networks Group Chairman/CEO Peter Rice about seeing if potentially there would be interest in a TV expansion of this X-Men brand,” Hawley continued.

“Peter was very excited about it and looped in Gina Balian [who heads up limited series development] at FX. She’s the one who brought it to me as a potential idea, and asked if there anything in this universe you’d be interested in. I’m not a huge comic person. I read a lot of X-Men growing up, but it’s not something that was my life-long dream to do something like this. But what’s nice is I just started the process, not even based on any of the characters from the universe, but I just started thinking about that world and if there is an interesting show to play around that idea of mutant-outsider identity.”

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