Join (L-R) Maggie, Marge, Lisa, Homer and Bart Simpson for the 21st season premiere episode "Homer The Whopper," of "The Simpsons" airing Sunday, Sept. 27 (8:00 - 8:30 PM ET/PT) on FOX. THE SIMPSONS ™ and © 2009 TCFFC ALL RIGHTS RESERVED. ©2009 FOX BROADCASTING

The Simpsons Executive Producer, Al Jean says to expect a super-sized episode for the kick off of the 21st season tonight.

Homer Simpson is cast as a superhero for Comic Book Guy’s new movie and according to Jean, he struggles with getting into shape.

The show was co-written by Seth Rogen (Knocked Up, Superbad) who brings his own twisted sensibilities to the animated series.

Season 21 of The Simpsons begins 8:00 p.m. ET/PT on Fox.

Click onto media bar for the full synopsis of Homer’s transformation troubles on The Simpsons from Executive Producer, Al Jean.