
Legion introduces the story of David Haller: Since he was a teenager, David has struggled with mental illness. Diagnosed as schizophrenic, David 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 the visions he sees might be real. He's based on the Marvel comics character Legion, the son of X-Men founder Charles Xavier (played by Patrick Stewart and James McAvoy in the films), first introduced in 1985.
Dan Stevens David Haller
Rachel Keller Sydney "Syd" Barrett
Amber Midthunder Kerry Loudermilk
Bill Irwin Cary Loudermilk
Aubrey Plaza Lenny Busker
Jean Smart Melanie Bird
Jeremie Harris Ptonomy Wallace / Mainframe
Hamish Linklater Clark DeBussy
Navid Negahban Amahl Farouk / The Shadow King
Katie Aselton Amy Haller
Jemaine Clement Oliver Bird
Lauren Tsai Jia-yi / Switch