Marvel has attempted live-action TV shows based on the X-Men before, most notably in the Generation X movie and the Mutant X series.Those were pretty terrible, and the mutants' story has largely been told through animation on the small screen. That's changing now with the live-action FX series, Legion, which Marvel hope will have the same level of impact as what they're doing over on Netflix.
FX has officially picked up Legion for a condensed 8-episode first season order, with plans for the series to debut next year. They've also released the first image of star Dan Stevens as David Haller, the schizophrenic, supremely powerful son of Charles Xavier and Gabrielle Haller. David has been struggling with mental illness all of his life, going in and out of psychiatric hospitals, until a chance encounter with a patient forces him to consider the voices and visions in his may be real.
Jean Smart, Aubrey Plaza, and Rachel Keller co-star with Fargo creator Noah Hawley running the show. Despite the presence of exec-producers Lauren Shuler Donner, Bryan Singer, and Simon Kinberg there is no connection between Legion and the X-Men movies. At least not yet. Marvel also has another X-Men spinoff series in the works, Hellfire, which is based on the notorious cabal known as the Hellfire Club.