Homerin on pelastettava maailma aiheuttamaltaan katastrofilta. Kaikki saa alkunsa Homerista, hänen lemmikkisiastaan ja tulvivasta lantasäiliöstä. Tuloksena on sotku, jollaista Springfieldin asukkaat eivät ole koskaan aiemmin kokeneet.
A small town is suddenly and inexplicably sealed off from the rest of the world by an enormous transparent dome. While military forces, the government and the media positioned outside of this surrounding barrier attempt to break it down, a small group of people inside attempt to figure out what the dome is, where it came from, and when (and if) it will go away.
