After a riot at a sci-fi convention, Mayor Quimby hires Homer as his bodyguard, and Homer witnesses the rampant corruption in town politics. When Homer takes a stand, he runs afoul of the Springfield mafia.

Bart finds a friend in his own sister Lisa after Milhouse moves away to Capitol City to live with his divorced mom. Meanwhile Homer goes into panhandling to buy anniversary gifts for Marge. Later on Milhouse returns and Bart goes back being friends with him.