As the saying goes, you know you’ve made it once you’re on The Simpsons. Well, after a few years climbing the ranks of stardom, Seth Rogen is finally there.

Much like the rest of his career, Rogen is taking charge. He co-wrote the script for his character in the 21st season of the acclaimed cartoon, becoming only the second celebrity to do so (next to Ricky Gervais.) The season premier, “Homer the Whopper”, aired on Sunday night, and featured Rogen as the gym trainer who helped Homer get in shape for his upcoming movie role as “Everyman”, written by the Comic Book Guy, Perez Hilton reports.

Other celebrities appearing on this season of The Simpsons inclue Chris Martin (Coldplay), Sarah Silverman, Anne Hathaway, Jonah Hill and Neve Campbell.

Rogen said The Simpsons has always been something of “a Holy Grail” and he can “die a happy man now” having made the credits of the show.

Rogen has been busy otherwise gearing up for his role as the Green Hornet, another screenplay he wrote alongside Evan Goldberg (Superbad, Pineapple Express). The film, directed by Michael Gondry (Eternal Sunshine of the Spotless Mind), was pushed back to a December 2010 release date.

Related posts:

1. Seth Rogen Made A Boner Joke At The Golden Globes
2. EA Tries Their Hand at The Simpsons Game
3. New ‘Simpsons’ Guests Include Sutherland, White Stripes

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