Ranking All 25 The Simpsons Season Finales

Season: 20

Remember the town of Ogdenville, who foolishly bought into Lyle Langley's monorail, just like Springfield? Well, Ogdenville is back in season twenty's finale Coming to Homerica, which is essentially the Simpson's take on the immigration debate.

In the episode, Krusty Burger (having been deemed the unhealthiest food around) opts to start selling the Mother Nature Burger, a vegetarian sandwich, in the hopes of improving its image. Soon, however, the whole town is sick from it due to tainted barley, and the blame is placed at the feet of Ogdenville's natives, who are of Norwegian ancestry, and rely on barley farming to float their economy. 

When a boycott of barley after the food poisoning incident cripples them financially, they begin moving into Springfield, doing odd jobs and minimum wage tasks until some citizens band together and opt to try to force them out, going so far as to build a wall.

Of course, unable to build the wall themselves, they hire the Ogdenville folk to build it for them - then wind up letting them back in in the end.

It's not exactly thinly-veiled social commentary, but it's not fully in your face either, and watching Chief Wiggum fail miserably at keeping illegal "immigrants" out of Springfield (to the point that they're walking right by him) is pretty amusing.