Legion Trailer: FX's Marvel Series Takes Look at 'Most Powerful Mutant Ever'

What the X, man?!

The first trailer for FX’s first Marvel series, Legion, finds Dan Stevens (Downton Abbey) living an X-traordinarily trippy existence — as someone who may be “the most powerful mutant ever.”

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Legion follows David Haller, a troubled young man who may be more than human. Diagnosed as schizophrenic, he has been in and out of psychiatric hospitals for years. But after a strange encounter with a fellow patient, he’s confronted with the possibility that the voices he hears and visions might be real.

Exec-produced by Fargo‘s Noah Hawley and set to debut in 2017, the series also stars Rachel Keller (Fargo), Jean Smart (Fargo), Katie Aselton (Casual), Jeremie Harris and Amber Midthunder (Banshee), with appearances by Bill Irwin (SVU) and Aubrey Plaza (Parks and Recreation).