Films That Focus on a Rivalry

I'm beginning to work on a short film that focuses on a rivalry between my two main characters, and I'm looking to find good movies that also have this focus so I can study them and learn from them to hopefully make my story better for my film. So far tomorrow I plan on watching the movies Rush starring Chris Hemsworth which focuses on the rivalry between James Hunt and Niki Lauda, and Warrior starring Tom Hardy which focuses on a sibling rivalry between two MMA fighters, or that's my basic understanding of the films. I'm looking for something that is a little more gray than the traditional protagonist-antagonist, where maybe the hero isn't so clear cut and one isn't just obviously a bad guy, another example is The Prestige which is a personal favorite of mine. Think more Harry Potter and Draco Malfoy than Harry Potter and Voldemort in terms of the dynamic between the characters. Yeah you might be rooting for one of them over the other because he's on the morally right side, but even the other character you would feel for and sympathize with as well.

If anyone has some good examples of movies like this for me I'd love to hear your suggestions I may even decide to revive my review thread and post my thoughts on them. Thanks to everyone in advance, hopefully I can learn a lot from these movies and also have a good time watching them!

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"Mikey and Nicky"

Recount (2008)

This is about the U.S. presidential race between George Bush & Al Gore and it stars Kevin Spacey, Laura Dern and John Hurt. It's not what you'd expect, at all ... it's surprisingly interesting and it's got a lot of documentary footage thrown in, to give the film some legitimacy, I guess you would call it. But it really does focus on both camps competing for the same prize. Though Gore and Bush are kind of played by actors, they are only shown from behind and stuff like that, for like ... a quick minute. Most of it's to do, actually with the teams campaigning for them. I first watched it as a sort of, "nothing else on" kind of thing and not expecting much at all, except to be put to sleep by it. But it was really good!

Well the X-Men films certainly have a lot going for them in terms of the conflict and strained friendship between Magneto and Professor Xavier, with Erik pretty much the hero, or anti-hero of First Class.

You might also find The Duellists interesting.

Johnny Guitar, Black Swan, What Ever Happened To Baby Jane? Dangerous Liaisons, Sisters, Autumn Sonata, Love Crime (and the remake by Brian de Palma, Passion), etc.

I especially quoted movies with rivalries between women (except Dangerous Liaisons) but it's not very important. The structure of these films and the psychology can be interesting to analyze.

I also advise you the book The Anatomy Of A Story by John Truby