|Original airdate:||February 8, 2017|
|Next Episode:||"Chapter 2"|
"Chapter 1" is the first episode of the first season of Legion.
David considers whether the voices he hears might be real.
- Dan Stevens as David Haller/Legion
- Kyja Sutton as Amy (8-10 yrs)
- Aubrey Plaza as Lenny Busker
- Bill Irwin as Cary Loudermilk
- Jeremie Harris as Ptonomy Wallace
- Katie Aselton as Amy Haller
- Amber Midthunder as Kerry Loudermilk
- Jean Smart as Melanie Bird
- Mackenzie Gray as Walter/The Eye
- Hamish Linklater as The Interrogator
- David Selby as Brubaker
- David Ferry as Dr. Dennis Kissinger
- Ellie Araiza as Philly
- Matt Hamilton as Ben
- Brad Mann as Rudy
- Quinton Boisclair as Devil With The Yellow Eyes
- James Wilson as High School Principal
- Jim Eliason as SWAT Team 3
- Kari Staten as Townsperson
Continuity and References to the Earth-10005
- David Haller/Legion is introduced.
- Summerland is introduced.
- Sydney Barrett is introduced.
- Lenny Busker is introduced.
- Ptonomy Wallace is introduced.
- Melanie Bird is introduced.
- Clark Debussy is introduced.
- Cary Loudermilk is introduced.
- Kerry Loudermilk is introduced.
- Charles Xavier/Professer X is heard in the background.
- Clockworks Psychiatric Hospital is introduced.
- Legion (and all his multiple personalities) made his comic book debut in 1985 in New Mutants #25.
- The different colored uniforms work by Clockworks Psychiatric Hospital patients are to classify a patient's level of risk of violence. Patients who wear white uniforms are of no risk of violence, yellow uniforms have a mild to moderate risk of violence, and red uniforms are of a high risk of violence.
- Several characters refer to an "incident at Red Hook." Red Hook is the name of the town next to Bard College, where Marvel character Jean Grey was buried. Jean Grey's father was a professor at Bard College and Jean Grey grew up in the area.
- Charles Xavier's voice can be heard in the background swirl of voices, early in the episode, but Patrick Stewart does not have an acting credit for the episode.
- Seems to be in the X-Men universe. David Haller was Professor X's son in the comics and was powerful enough to create the Age of Apocalypse storyline.
- David is seen in a wheelchair early on in the episode in the hospital. This is a reference to his father in the comics, Professor Xavier.
- When Syd and David switch bodies, she is able to tap into the powers on one of his personalities. Known as Personality #5 in the comics, Personality #5 is a godlike mutant who describes himself as "The One True Legion". He has the ability to warp both time and reality which would explain how Syd was able to change the structure of the patients rooms, leaving no doors, as well as, trapping Lenny in the wall.
- In one of the early scenes of David growing up, there is a group of people surrounding him and shouting at him. The group is not real and are actually David's personalities fighting in his mind.
- During the episode there are various people that only David can see, such as: the old couple when talking to his sister, and the man in the greenery when he's sitting with Lenny. These are not actually delusions and are, in fact, some of David's personalities.
- To depict David Haller losing control of his abilities in a kitchen, actor Dan Stevens was filmed separately from the practical effects, with the images layered together to create the final, slow-motion sequence.