The Lawndale File

"The Lawndale File" was the eleventh episode of the third season of Daria (episode number 311). It first aired on MTV on August 4th, 1999 and was written by Peter Elwell. This episode is sometimes mis-written as "The Lawndale Files" (per the TV series The X-Files).

Summary
A mysterious pair of government agents arrive at Lawndale High, Trent's playing cheerful music, Quinn's changed up her wardrobe. . . . Something strange is happening in Lawndale.

Trivia
This episode features the return of Artie from "Esteemsters."

The government agents are visual pastiches of Mulder and Scully from The X-Files.

Sick, Sad World, for the first and only time, reports on something Daria was involved in.

"The Lawndale File" and Fanfic
"And I on the Opposite Shore Will Be" by The Angst Guy: a science fiction fanfic following on from the end of this episode

"It's That Guy" by RLobinske: another twist on the ending

"Not So Different 37: 'Fury, Signifying Nothing'" by J-D: part of a Gender Swap series, with the sinister agents coming after "Sonny" Morgendorffer