'The Simpsons' will kill off Bart this Halloween

After 574 episodes and 26 seasons, Sideshow Bob will finally get his wish.

In a long-running Simpsons gag the diabolical character (voiced by Kelsey Grammar) tries fruitlessly to kill Bart Simpson, only to fail in one way or another. But during a panel at the ATX Festival this weekend, Simpsons producers revealed the unthinkable: Bart will actually get killed off in the show's upcoming 27th season.

Naturally, it's all happening on the annual Simpsons Halloween special. There's no way Bart will be departing the show after the earth-shattering act (or so we're guessing) so the Simpsons will have to get crafty to explain his resurrection. An alternate Springfield afterlife, perhaps?

Luckily, neither of the characters are voiced by Harry Shearer, who departed the Simpsons cast earlier this year.