Fox Mulder often turned to his friends, The Lone Gunmen, for help on The X-Files, but the trio was abruptly killed off during season 9. Over the course of its eleven seasons on the air, The X-Files played host to lots of great supporting characters, including people like Deep Throat, Alex Krycek, and Morris Fletcher. Near the top of the list, though, is Richard Langly (Dean Haglund), Melvin Frohike (Tom Braidwood), and John Fitzgerald Byers (Bruce Harwood), collectively known as The Lone Gunmen.
Named in reference to the infamous assassination of President John F. Kennedy, The Lone Gunmen were a tech-inclined trio that also believed in just about every possible conspiracy theory. In real life, that would probably be a bad thing, but in the shady world of The X-Files, just because a character was paranoid didn't mean evil people weren't out to get them. Oddly enough, it wasn't black-suited government hitmen who eventually took out The Lone Gunmen; it was instead a rare instance of direct heroics.
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In theX-Files season 9 episode «Jump the Shark,» The Lone Gunmen sacrifice their own lives in order to stop the release of a bio-weapon that would've killed thousands, if not millions. It was a noble but sudden and a bit harsh death for the popular trio, but it turned out there was no future for them as recurring players on The X-Files. After the quick cancellation of The Lone Gunmen spinoff series due to low ratings, the Fox network turned on the characters and didn't want them back on The X-Files. This even extended to the point where Fox didn't want to allow creator Chris Carter to even bring them back to die.
This left Carter and «Jump the Shark»
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