The Simpson's 500th episode

The family is exiled from Springfield to a community of outsiders where they meet Wikileaks founder Julian Assange.

Fox TV said Assange recorded his lines from the UK, where he is fighting extradition to Sweden over alleged sex offences - charges he denies.

The animated comedy is in its 23rd season, making it the longest-running prime-time scripted programme on TV.

The show is contracted to run for another two seasons, which will bring it to 559 episodes.

Previous guest voices on the programme have included former British Prime Minister Tony Blair, graffiti artist Banksy and novelist Thomas Pynchon.

The Simpsons' executive producer Al Jean told Entertainment Weekly that series creator Matt Groening heard a rumour that Assange was interested in guest-starring on the series.

"We asked our casting director Bonnie Pietila - who had been able to unearth Thomas Pynchon and got Tony Blair to do the show - to find Mr Assange. And she did," Jean said.

Jean added the show's creative team realised Assange was "controversial" but they avoided delving into "the legal situation that he's in".

"We wanted to make sure it was satirical, and he was willing to do that," he said.

http://www.bbc.co.uk/news/entertainment-arts-17092968