Onibaba
Had this on my watchlist for some time now, but seeing Willem Dafoe put it in his top 4 I finally came around to watch it. Glad I did. The soundtrack, the tall grass, and the lighting on the faces are all superb! Quite a simple story of Envy, poverty, war, and lust with sprinkles of old-school horror. A movie that grips you the further you get into it, the 2nd half is especially good.
Those grass shots with the sound effects/music are both chilling and awesome.
Edit: Had to edit this to a 5/5, because it still sits with me after a few days. so bare bones, yet so haunting.