The Simpsons The Simpsons

Has Springfield finally had enough of the Simpsons clan? On the long-running animated series' 500th episode (titled "At Long Last Leave," airing Sunday at 8/7c on Fox), Homer and family discover that they weren't invited to a secret town meeting. "The point is to kick them out of town for all the crap they've pulled over the last 500 episodes," says Simpsons executive producer Al Jean. "We explore their emotions as they find out that everyone hates them."

After the Simpsons are evicted from town, they're forced to live off the grid in a shantytown outside Springfield. Homer (Dan Castellaneta) and Marge (Julie Kavner) try to make their way back into Springfield, but are met only with hostility from their ex-friends and neighbors. That's when the Simpsons decide to make the best of their new situation and settle into their new home.

In a treat for true Simpsons buffs, Jean promises appearances from several rarely seen characters. Guest stars include controversial WikiLeaks founder Julian Assange, who presumably shares a top-secret dossier on the Simpson family's exploits. The show also tapped performer Alison Krauss to record a special bluegrass version of The Simpsons theme song, which will be heard both within the episode and during the end credits.

Jean calls the 500th episode "a tribute to people who love the show." The next milestone for the series is its 25th season, in 2013. Jean is also gunning to beat Gunsmoke's all-time record of 635 episodes: "I don't think the 500th episode of Gunsmoke had any international cyberspace leakers on it."

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