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That "Simpsons did it, Simpsons did it!" episode of South Park would have you think the going-strong-since-'89 Fox series has done it all. But Season 28 will tick a new box with what will somehow be its first-ever hourlong episode, featuring Empire's Taraji P. Henson and Key & Peele's Keegan-Michael Key.

The episode, which will premiere in January, is a hip-hop tribute to The Great Gatsby called..."The Great Phatsby." 

Simpsons executive producer Matt Selman told Entertainment Weekly:

“This was just going to be a regular episode, but the table read went so well, in a fit of passion and excitement and ambition and excess, we decided to supersize it. And we haven’t done a huge amount of stories in the world of hip-hop and rap culture, so we just went for it.”

Henson will show up as a Simpsons-fied version of her Empire character, Cookie, named Praline. Key will play a rapper called Jazzy James.