Season 5, Episode 11: “Kill Switch”
Original Airdate: February 15, 1998
“Kill Switch” is an old story gussied up with new tech. Of course, the tech is from 1998, so the new tech is now not so new, so it's good for the old story that it is an old story, because it's a decent old story—ever heard the one about the machine that got smart and then got even? Written by cyberpunk godfathers William Gibson and Tom Maddox, “Kill Switch” is a fresh take on the show's usual slime-and-evolution monster of the week, the rare one-off that doesn't include a scene where Mulder refers to some wacky event that happened a century ago. Here is an X-File that doesn't yet have a file.