Bart Simpson will be killed off in 'The Simpsons'.

The Simpsons

The Simpsons

The cartoon schoolboy is set to fall victim to a diabolical plan by arch rival Sideshow Bob in an upcoming episode, which will be broadcast in the autumn.

The show's executive producer Al Jean revealed the news during an ATX Festival panel in Texas, where he admitted he was inspired to air the dramatic scenes because he felt "frustration" when the Coyote never killed the Road Runner in the animated children's show 'Looney Tunes'.

He said: "I hated frustration comedy so we'll scratch that itch.

"So Bob will finally somehow actually execute Bart - and then won't know what to do with himself after his life's mission has been accomplished."

However, fans can rest assured the murderous scenes will not mean the end of the show or the son of Homer Simpson, as the episode is a one-off Halloween special, meaning he will be back to normal in subsequent episodes.

Kelsey Grammer, 60, will return to play the evil genius, who first hit screens in 1990 before beginning his quest to murder Bart in 'Cape Feare' in 1993, having also attempted to kill Bart's aunt Selma the previous year in 'Black Widower'.

Producers sparked fears Krusty the Clown could be facing the axe last year when they teased the death of a show favourite in "Clown In The Dumps," although it was later revealed it was Krusty's father, Rabbi Hyman Krustofsky - voiced by Emmy winner Jackie Mason - who was set to die on screen.