Mr. Donnelly kicks Chett out of the house until he can find a job. There's nothing for Chett to do, so Lisa zaps an "A Man's Man's World" and creates a monster truck-cigar-jerky-paintball store for Chett. But Lisa accidentally zaps two alley rats, Rhett and Mickey, into humans who want to wipe out the human race by using the plot from Invasion of the Body Snatchers with Chett helping them.