You have to show a seventeen year old boy a movie that he's gonna like

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Im biased because I love Westerns but

The Good, the Bad and the Ugly
Once Upon a Time in the West

Or easily a dozen other of my favorite Westerns that comes from the 60s and 50s and a few from the 70s.

But the majority of people, especially young people now dont care about westerns so I would go with something like The Warriors. I think even modern teens would dig something like that.
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