"Legion" TV Series is now scheduled to premiere on FX starting February 8, 2017 at 10 p.m. In the newest trailer, David Haller (Dan Stevens), the son of Professor Charles Xavier, is treated for schizophrenia but the treatment appears to be working backwards. Since he is the son of Professor Xavier, it opens the door for a possible cameo.

Haller, according to Deadline, has been in and out of psychiatric hospitals for years but talking with another patient the diagnosis might be the beginning of something big. He ends up becoming one of the most powerful mutants in the X-Men universe because his multiple personalities make him a mutant not to be messed with. "Legion" TV Series follows his daily chronicles as he gains allies and makes enemies.

"Legion" TV Series star Dan Stevens is most famous for his portrayals as Matthew Crawley in the drama "Downtown Abbey" and as David in the thriller "The Guest." He will next be seen in "Beauty in the Beast."

Director Bryan Singer said "Legion" TV series is part of the X-Men cinematic universe but the series is said to be a stand alone also. Since David is the son of Professor X, there is no word on how this will connect him in the happenings of the X-Men movies. There are rumors that "Legion" might become a precursor to X-Men shows that would end up connecting it to X-Men movies in the future.

According to the Hollywood Reporter, "Legion" TV Series also stars Amber Midthunder, Jeremie Harris, Bill Irwin, Katie Astleton, Aubrey Plaza and Rachel Keller. Noah Hawley is the creator of the series and he is also executive producing it alongside Lauren Shuler Donner, Bryan Singer, Simon Kinberg, Jeph Loeb, James Chory and John Cameron.

Check out the latest "Legion" TV series trailer here: