After the agents meet Deep Throat in the empty warehouse, Scully returns to Georgetown University. The establishing shot shows the outside of the building from the Prospect Street Entrance. This near-exact view can be found in Google Streetview, but the entrance sign is now blue and white instead of light brown and black. The street view location is the corner of Prospect St NW and 37th St NW (DC 20057).
The trivia items below may give away important plot points.
The closing scenes are almost identical to the closing scenes of The X-Files: Pilot (1993). Scully is in bed and sees her digital clock turn from 11:21 to 11:22. Mulder calls and they talk. The scene cuts to The Cigarette Man, who places an object in the vast Pentagon vault. Both episodes end with the door of the vault slamming shut and the camera showing the sign on the door: "In Case Of Fire Or Emergency / Know Your Exits / PENTAGON / Evacuation Procedure."