He's been trying and failing to end Bart Simpson for a quarter of a century. Now The Simpsons's creators have revealed that Sideshow Bob will finally get his wish.

The clown, voiced by Kelsey Grammar since 1990, has fixated on Bart Simpson as the cause of all his problems since the episode Cape Feare in 1993. He has come close to murdering his nemesis on a number of occasions, but will finally win the day in the programme's forthcoming 27th series.

"I'm one of the people who always wanted the Coyote to eat the Road Runner, so you can see where this is going," executive producer Al Jean told Entertainment Weekly.

"I hated frustration comedy so we'll scratch that itch on the Hallowe'en show."

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But this being The Simpsons, it won't work out quite as planned. After killing Bart, Bob will find himself at a loose end having achieved his life's goal – and being a self-contained Hallowe'en episode, Bart will spring back to life after the advert break anyway.

The new series will also see the return of Spider Pig, and an episode based on the Oscar-nominated film Boyhood, focused on Bart.

In another episode, Homer is diagnosed with narcolepsy, leading to he and Marge separating, and Homer falling in love with his pharmacist, voiced by Girls star Lena Dunham.