BART's (Nancy Cartwright) science fair project, a mechanical baby seal, outshines LISA's (Yeardley Smith) brainy asteroid model and becomes a popular pet among the retirement home patrons. Meanwhile, HOMER (Dan Castellaneta) gets a new and eager assistant Roz (guest voice Lynch), but when Homer quickly loses his job to her and discovers her evil past, he and FLANDERS (Harry Shearer) team up to reveal her true dark colors in the all-new "Replaceable You" episode of THE SIMPSONS airing Sunday, Nov. 6 (8:00-8:30 PM ET/PT) on FOX. (SI-2221) (TV-PG D, L, V)

Voice Cast: Dan Castellaneta as Homer Simpson; Julie Kavner as Marge Simpson; Nancy Cartwright as Bart Simpson and Nelson; Yeardley Smith as Lisa Simpson; Harry Shearer as Skinner; Pamela Hayden as Milhouse; Tress MacNeille as Dolph

Guest Voice Cast: Jane Lynch as Roz