This is from a Wiki plot summary for a season 17 episode I picked at random.
The Simpsons enjoy spending time in the village, and they continue to keep Bob's past a secret. However, when Lisa gets drunk at a party, she starts to spout off about him being an attempted-murderer. He leads her away from the table, but as she stumbles backwards, she rips off his suit and everyone can see that underneath is his prison uniform. The village finds out the Bob is an attempted killer, and they sack him as Mayor. The Simpsons take off in the fixed car, and Bob swears vendetta on them.
Didn't Lisa already once foil Sideshow Bob's effort to become Mayor leading to a swearing of a vendetta and whatnot? Did the Simpsons pull a "Simpsons did it"?
Anyway, the plots have always been rather silly, its was the brilliant jokes that made the show sparkle. Homer works for a Bond villain shouldn't be one of the greatest works of art in all human history, and yet somehow it is.