12 Main Character Deaths That Killed Great TV Shows

10. Fox Mulder (The X-Files)

Episode Of "Death": S07E22 "Requiem"

While The X-Files never technically "killed off" our favorite conspiracy-mad FBI agent, its on-again-off-again treatment of the character over the next two seasons sorta made us wish it had.

It was thought at one point that the Season 7 finale, Requiem, might well be the series finale; despite this, the writing staff perversely decided to throw in a whole bunch of cliffhangers. I'm not talking ambiguities and open-endings - like, was Tony Soprano shot and killed in the final moments of the finale, or will he live the rest of his life in fear? - but setting up whole new plot threads: The CSM dead?! Scully pregnant?!! Mulder sucked up into the sky by a UFO having just completed his life's work of discovering proof of alien intervention on Planet Earth?!!!

And then the series got renewed. Having ousted one half of its core duo, Robert Patrick was brought in as Special Agent John Doggett: serious, skeptical, he was everything his predecessor wasn't. For the next 41 episodes, though, the ghost of Mulder loomed large over the series, not helped by his periodic return: he appeared in half the episodes of Season 8 and only two in Season 9.

Content to effectively treat the character as dead when it was convenient to do so, Annabeth Gish joined the show as Monica Reyes and The X-Files continued to stagger on until The Truth.

In short: when your show's appeal is largely predicated on the male/female, believer/skeptic, will they/won't they sexual chemistry of your two leads, it's probably best not the split them up and bury one of them in a secret military facility. Just a thought.