The Simpsons Movie (PG-13)
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This is of course based on the TV series The Simpsons, which is one of the best shows ever. And the movie's pretty good too. It's impossible for me to say if it would really stand on its own if you're not familiar with the series, since I, like everyone else in the world, am familiar with the series. But I'm guessing... not so much. It's amusing, but it does feel to me like it relies pretty heavily on familiarity.
Anyway, Lisa is concerned about the environment, mostly a local lake that everyone in town dumps all kinds of waste and trash into, and stuff. She also meets an Irish boy named Colin who's into the environment, and there's a potential romance there, but that part of the plot feels kind of tacked on. There are of course other intersecting plotlines, like Bart thinking Ned Flanders would make a better father than Homer, and Homer taking in a pig as a pet. And dumping the pig's waste in the lake, which tips the scales of environmental disaster. And then this guy Russ Cargill, the head of the EPA, gets a giant dome put over Springfield.
So everyone's upset about being trapped in the town, and when they find out Homer was responsible, they form an angry mob, and chase the family, who manage to escape the dome, and move to Alaska. And eventually Cargill decides he has to drop a bomb on Springfield, while keeping the outside world from knowing Springfield even existed in the first place, which is just ridiculous. But whatever. Um, the Simpsons find out about this and Marge and the kids want to go back to save the town, but Homer wants to stay, because he likes their new life and is upset about everyone back in Springfield hating him.
There is a rather emotional scene of Homer watching a videotape Marge had left for him, I liked that bit. And so he goes after them. And he has an epiphany and stuff. So he goes back to Springfield to try to save the town and reconnect with his family. And that's all I can think to say. Yep, not a bad movie.