1x24 The Erlenmeyer Flask (Season Finale)
Scully: You don’t know that this isn’t just a game with him. He’s toying with you. Rationing out the facts.
Mulder: You think he does it because he gets off on it?
Scully: No. I think he does it because you do.
Mulder: You know, from day one, this has always been on your terms. I’ve gone along. Been the dutiful son. But maybe this time, we can just cut out the Obi-Wan Kenobi crap and you can save me the trouble.
Deep Throat: I fear you’ve become too dependent on me.
Mulder: Let me tell you something. I’ve got plenty to do without chasing down your vague leads or trying to decode your circular logic. Maybe it’s you who’s become too dependent on me… on my willingness to play your games.
Deep Throat: Mister Mulder?
Deep Throat: Don’t give up on this one. Trust me. You’ve never been closer.
Dr. Carpenter: Agent Scully.
Scully: Oh, Dr Carpenter, I fell asleep.
Dr. Carpenter: I’ve done some work. These are the DNA sequences from the bacteria sample you brought in. You seem to know something about molecular biology. Do you know what you’re looking at?
Scully: Yeah, I think these are genes.
Dr. Carpenter: Right. They’re called base pairs. Each pair is made up of something called a nucleotide. Only four nucleotides exist in DNA, four. And through some miracle of design that we have yet to fathom, every living thing is created out of these four basic building blocks. What you’re looking at is a sequence of genes from the bacteria sample. Normally, we’d find no gaps in the sequence. But with these bacteria we do.
Scully: Why is that?
Dr. Carpenter: I don’t know why. But I tell you, under any other circumstances my first call would have been to the government.
Scully: What exactly did you find?
Dr. Carpenter: A fifth and sixth DNA nucleotide - - A new base pair. Agent Scully, what you are looking at, it exists nowhere in nature. It, would have to be by definition… extraterrestrial.
Deep Throat: Trust…trust no one.
Scully: What are you going to do?
Mulder: I’m… not going to give up. Not as long as the truth is out there.