JUDAS PRIEST singer Rob Halford will guest on an episode of The Simpsons this January.

Entertainment Weekly reports the episode will feature a decade-old spec script written by writer-director-producer Judd Apatow, who is collaborating with the animated series in front of the microphone as well.

The Apatow & Friends showcase, which is titled "Steal This Episode", will boast Will Arnett as a guest star, frequent collaborators Leslie Mann, Paul Rudd and Seth Rogen, plus Channing Tatum.

Fed up with movie theaters, Homer is taught by Bart how to illegally download films, and he starts screening them in his backyard for folks in Springfield.

“Even though Homer is stealing, he’s doing it for the community, he’s doing it out of the goodness of his heart,” says executive producer Matt Selman.

Alas, an overzealous FBI director in charge of anti-piracy (Arnett) doesn’t quite see it that way and sets his sights on Homer.

How do our celebrity guests fit into the plot? One of the movies that Homer shows is a This is 40-esque Apatow dramedy titled Life is Funny that stars Mann and Rudd, who joined forces in Knocked Up and This is 40.

Halford winds up singing a parody of the JUDAS PRIEST classic 'Breaking The Law' in an effort to nab Homer, while Apatow testifies against our patriarch “with a hilarious, self-important speech about Hollywood people,” says Selman.

Halford and JUDAS PRIEST are currently working on the follow-up to 2008's "Nostradamus."

This past spring, JUDAS PRIEST released the 'Epitaph' live DVD, which captures the final show of the band's last ever world tour, filmed at the Hammersmith Apollo London on May 26, 2012.

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