The X-Files Season 11: 10 Things We Learned From 'This'

"Am I dead? If I am, they know that I know" says the ghostly digital version of Langly early in This.

As much as it doesn't matter if Richard Langly is physically dead or not (in theory, he could be in a coma somewhere, and his digital consciousness could still be alive), the key to this episode is that he is alive. In digital form. Point being, for the episode to work you must accept that digital Langly is alive, conscious, self-aware, and aware that he is in a simulation.

He's a copy who branched off from the original at some point, but he knows who Fox Mulder is, and knew (eventually) to reach out to him.

If digital Langly isn't alive, then he likely never figures out he's a slave. It's the entire question of "what makes something alive" that drives This. Langly, we learn, had a love interest, Karen Hamby. A professor of mathematics at Semple Technical Academy in Maryland. The pair agreed to transfer themselves to digital copies in order to be together forever, well before Langly's physical death. However, Langly has figured out the world he's in is digital - the sun's warmth is missing, for one. And he knows the world's greatest minds are being enslaved after "death" there. No one else realizes they're in a simulation.

There's a bit of a Matrix vibe, only we're seeing things from the "real" world. Although the episode very subtly suggests that Mulder and Scully themselves could be in a simulation (but that's a theory for another day).