WASHINGTON — Ay, caramba!

Bart Simpson will reportedly meet his demise at the hands of longtime nemesis Sideshow Bob this fall on an episode of “The Simpsons.”

Entertainment Weekly reports Kelsey Grammer will return to voice Sideshow Bob, the diabolical character who began as a sidekick of Krusty the Clown.

But don’t “eat your shorts” just yet. The murder will happen on the annual Halloween episode “Treehouse of Horror,” which operates under a different universe.

That means Bart will likely return to normal after his Halloween death.

Producers also tell Entertainment Weekly that a fan favorite from “The Simpsons Movie” — Spider Pig — will return during the upcoming season.

The season is entering its 27th season on FOX.