As an actor, Jim Rash has the market on playing characters with sexual perversions down cold. In his over 15 years as an actor, he's played everything from, in his own words, mere patronizers of bordellos to downright creeps. His current role is no exception. As the enthused Dean Pelton on the cult NBC sitcom "Community," which returns for its third season tonight, Mr. Rash lets his character's freak flag fly with hyper-flamboyant outfits and a touchy-feely approach to his students.

As a screenwriter, however, Mr. Rash...