‘Legion’ Theory: Could Syd Be a Creation of David’s Mind Made Real by His Powers? (Spoilers)

[...] it’s during this attempt to find out what’s really going on with David that “Legion” creator Noah Hawley hits viewers with evidence that may well confirm a theory that’s floated around since the start of the show: that Syd, the body-switching mutant who has become David’s girlfriend, isn’t real.

“Legion” has spent its entire run so far toying with the viewer’s notion of reality within the show, because we’re seeing just about everything from David’s point of view.

Syd has always been a bit suspect as a character, but her time spent in David’s mind suggests more than anything that she’s actually a part of him.

When the other characters can’t see the threatening elements of David’s subconscious, like the Devil with the Yellow Eyes, Syd can.

Where the other characters venturing into David’s mind are passengers or tourists, in Episode 3, Syd is wholly in tune with what’s happening there.

[...] we’ve already seen David’s reality-bending powers at work.

He can teleport people and objects through walls and over distances, especially when he’s in trouble.

Why would the Interrogator lie to David about Syd’s records if he’s trying to track her down, and if his organization is the one that is covering up her existence?

[...] if David really can alter reality, it seems easy enough for his mind to supply Syd with memories and backstory, while also doing enough adjustments to the perception of people around him to make her seem real.

There are no records of Syd in the show because David has never had occasion to worry about the bureaucracy that would be involved in keeping track of her.

[...] her continued appearance to David, even after she dies, makes more sense if she’s always been part of his mind.