FX Networks' upcoming X-Men series "Legion" will star Dan Stevens, Aubrey Plaza, and Jean Smart.

"Fargo" producer Noah Hawley wrote the pilot for "Legion," and will also serve as the project's executive producer, Marvel's official website reported. The series, which follows the story of a troubled young man, will kick off production in March.

Stevens, of "Downton Abbey" fame, is portraying "a haunted man" named David Haller, who was "diagnosed as schizophrenic at a young age" and will try "to find his way back to sanity, but he's getting tired and is about to give up when he meets the girl of his dreams," Marvel's website wrote.

According to Entertainment Weekly, David has been going in and out of numerous psychiatric hospitals when he discovers that the voices and visions inside his head might be real. He is actually the mutant son of X-Men leader Professor Charles Xavier.

"Parks and Recreation" star Plaza will play David's friend Lenny, "who despite a life of drugs and alcohol abuse, knows that any day now her life is gonna turn around, which gives Lenny the likeable energy of the impossible optimist despite her rough demeanor," Marvel added.

Smart (of "Fargo") portrays Melanie, a "nurturing, demanding therapist with a sharp mind and unconventional methods," the news outlet further reported.

The three will be joining "Fargo" actress Rachel Keller. Marvel's website describes Keller's Syd as a "self-sufficient and street smart" woman "uses her sharp and prickly demeanor to protect her soft core, because even though it makes her a sucker and puts her at risk, she still believes in happily ever after."

Even though the lead of "Legion" hails from the "X-Men" universe, fans should not expect the FX series to crossover with the popular film franchise. According to an FX head, "Legion" takes place in a parallel universe where the U.S. government was just beginning to notice the existence of mutants, but the public is still in the dark, Entertainment Weekly reported.

"It's not in the continuity of those films in the sense that the current 'X-Men' films take place in a universe where everybody on planet earth is aware of the existence of mutants," FX boss John Landgraf said at the Television Critics Association press tour last month, as quoted by Entertainment Weekly. "I wouldn't foresee characters moving back and forth because they really are parallel universes."

Joining Hawley as executive producers are popular "X-Men" and Marvel producing talents: Lauren Shuler Donner, Bryan Singer, Simon Kinberg, Jeph Loeb, Jim Chory, and John Cameron, the news outlet listed. "Legion" is expected to premiere sometime this year.