Wonderful thread!
I have to say B plots sometimes are more important than the A plot because it gives the movie depth and credibilty. Also, it supports the movie while the A plot is doing it's thing.
I have to say that while 300 is not historically accurate (thank goodness since it wouldn't have been as much fun!) I loved its political B plot. It's one thing to go, fight and die as a hero, it's another to have to stand up to a bunch of hostile and powerful people and argue your way out of a mess. Some would say dying is the easy part.
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