After 26 years, Harry Shearer and The Simpsons have parted ways. The actor has had a complicated relationship with the show for a large bulk of that time, and he announced that he was leaving on Twitter, citing an inability to work on other projects:

After 26 years, any relationship starts to show wear and tear, but Shearer has had issues with The Simpsons for well over a decade. In 2001, he spoke with East Bay Express about the show's wavering quality:

It depends on the script. There are writers' names that, when I see them on a script, I get very happy and look forward to the week, because I know there's gonna be a pretty sound script that is satirical but smart and not just sort of pointlessly parodic, if I may. And there are other writers' names that make my heart sink. It's sort of unavoidable this far along that that's going to be the way it is.

Shearer's voice talent made much of Springfield what it is, and we have him to thank for Mr. Burns, Waylon Smithers, Ned Flanders, Reverend Lovejoy, Kent Brockman, Principal Skinner, Rainier Wolfcastle, and a whole battalion of other characters.

During the cast's appearance on Inside the Actors Studio, Shearer held court as Burns, Smithers, Skinner, and Wolfcastle:

Those characters will remain, but they won't be the same. Alan Sepinwall spoke with Simpsons showrunner Al Jean, who confirmed that a replacement actor (or actors) will be brought in. "Burns and Flanders will not die," he says. "They are great characters and will continue."

Considering the network has threatened to replace the voice actors during previous contract negotiations, this move isn't surprising. It sure is disappointing, though.