Geez, there's an awful lot of people who don't seem to be reading the topic title before they answer.
As for me, that answer's easy,
Cadence with Martin and Charlie Sheen. It's set in West Germany on an Army base in the early 1970s. Charlie plays a malcontent who winds up in the stockade with some very tough customers and suddenly realizes he's not the toughest guy but he is the only white guy there. He soon runs afowl of the Stockade's master sergeant played by his father, Martin. Charlie's battle with Martin draws him closer to his fellow prisoners and he finds a part of himself he didn't know existed and leaves the stockade a stronger, more thoughtful man.
I knew those people - I lived that life. That movie speaks to me perhaps more than any other of any kind because it is so personal for me.