The X-Files - Season 9 Episode 4 4-D The truth is out there.
Overview: During a stakeout of murderer Irwin Lukesh, Doggett sees Reyes attacked by Lukesh, but then we see Reyes and Doggett in her apartment, apparently both fine. Elsewhere at the same time, Doggett is shot and Lukesh identifies Reyes as the shooter. While Reyes is asked for her badge and gun by A.D. Follmer, and Doggett lies in hospital near death, the conflicting circumstances of the stakeout and Doggett's shooting do not add up and it becomes clear that Lukesh possesses the power to switch between parallel universes and alter the events in each.
Comment
I can't believe I'm the only idiot writing an X-Files review here. Anyway, I still don't understand Piper Maru, it was a good episode but not really worth the praise it gets, and let's be honest, the Monster of the Week episodes were always better than the Mytharc ones... ... mostly better. There was were some pretty darn good mythology episodes, and there were ones like Piper Maru that were OK but not great. It was probably the ultimate television drama and an influence to everyone that wanted to achieve greatness on the small screen. It really showed what you could do with a one hour time slot and we were all blessed to have this done, not only because it was done so well, acted so well, and written in a way that invested the audience, but because it pathed the way for people that wanted to achieve that level of greatness. Television got better because of the X-Files, movies got better... and then politics came and it all sucks now, but for a little while, the X-Files raised the bar for everything.