Mulder: In four years I have shared my partner's passionate search for the truth and if my part has been a deception, I have never seen her integrity waver or her honor compromised. But now I ask her to lie to the people lying to us -- a dangerous lie to find the truth -- to find the men who would be revealed at its enemy, as our enemy, as the enemy within.
Scully: Mulder, how long has this been going on?
Mulder: Maybe since the beginning, since you joined me on the X-Files.
Scully: That would mean that for 4 years we've been nothing more than pawns in a game, that it was a lie from the beginning. Mulder, these men... You give them your faith and you're supposed to trust them with your life.
Mulder: There are those who can be trusted. What I need to know is who among them is not. I will not allow this treason to prosper, not if they've done this to you.
Scully: Mulder, we can't go to the Bureau making these accusations.
Mulder: No, but as they lie to us, we can lie to them. A lie to find the truth.