In March 2001, FOX began broadcasting "The Lone Gunmen," a series spun off from "The X-Files." Featuring as its main characters the three conspiracy-busters from the mother series, it was supposed to be a move in a more comic direction. Unfortunately, the show soon introduced an annoying buffoon character as a foil to the "gunmen," and the series tanked not long after that. The pilot, however, became rather interesting in hindsight. A crucial plot element, leading to the episode's climax, was this interesting element: the realization of a terrorist plot to hijack an airliner and to fly it into the World Trade Center.
I'm not implying that anybody knew that somebody was actually going to commit essentially that same act later, but it's interesting to realize how, as a plot on a conspiracy-inspired comedy series, nobody would have considered it a serious threat even if they had seen this episode before 9/11 happened.
The clip is just the juicy bits of the plot. If you want to see the whole episode, go here
, in that order if sequentiality is important to you.