When we learned Season 3 of FX's Legion would be its last, it followed with the announcement that David Haller's estranged father Professor Charles Xavier, leader of the famous X-Men, would be portrayed by Game of Thrones actor Harry Lloyd.

Although Xavier's presence was hinted at in previous seasons, series creator Noah Hawley confirmed the process of acquiring the rights for the character and his plans for Professor X in Season 3.

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"We know enough, even in the mythology of the show, to know that when David was born his father went off to fight [Amal Farouk] and kick Farouk out of his body," Hawley told TheWrap. " And so I think what we're going to explore, is that story."

Although Charles Xavier was portrayed earlier by Patrick Stewart and currently by James McAvoy, he was always part of the original plan for the series, and Hawley stated that Legion's unique status outside of current X-Men continuity helped with negotiations with 20th Century Fox.

“The good thing with Legion is that our reality is so detached from the comics — or anything — because it’s David’s subjective experience,” he said. “The tesseracts in his reality doesn’t really have to linearly tie to anything we’ve seen before.”

In Season 1, David learned his schizophrenia was a result of his manifesting mutant powers, and that his father's battle with Farouk, also known as the Shadow King, had unfortunate consequences that would dramatically affect his life. Losing his physical body to Xavier, the Shadow King managed to cheat death by latching onto David's mind when he was a child. Unaware that his enemy was keeping close, Xavier and his illegitimate lover Gabrielle tragically sent David away in hopes that the distance would make the child less of a target.

"At a certain point, his parents felt like the child was in danger and so they gave him to be raised by someone else," Hawley explained. "Not because they didn't want him, but for his safety, without realizing that already he had been compromised."

RELATED: How the Shadow King Retroactively Fought Against Charles Xavier

Under the guise of multiple identities within David's consciousness, Farouk tried and failed to take control of David's mind. His consciousness was ejected, but he remained a prominent threat in Season 2, where David and his allies struggled to prevent Farouk from returning to his original body. Although they failed, the Shadow King's full power was no match for David, who defeated him yet again. However, David's more sinister personalities remained, leaving the audience with the impression that we've been rooting for the villain all along.

Legion returns to FX in June. The series stars Dan Stevens, Rachel Keller, Jean Smart, Bill Irwin, Amber Midthunder, Jeremie Harris, Aubrey Plaza, Jemaine Clement, Hamish Linklater and Navid Negahban.