City of God (2002) - Brazilian epic crime movie about gangs in the Cidade de Deus suburb of Rio de Janeiro. Not obscure at all but lots of English speakers haven't seen it.
klassyCome and See (1985) - About a Belarussian boy who joins the resistance against the invading Nazi Germany during WW2. No question about it, this is the most creepy, insane and terrifying war-movie I've seen yet.
Lots of people don't know that Belarus lost a higher percentage of its population during WWII than any other country. Belarus lost twenty-five percent of its entire population during the war. Come and See is an absolutely brutal and necessary recreation of what that was really like.