[More like 4.5] I got to know this movie thanks to a list here on MUBI. I was mostly impressed by two key elements: how keen and innovative the technique is (e.g. the phase-contrast scenes are used well), and how compelling a 3h-long plot could be. It must have been thanks to elaborate character building. There are minor plot holes, but I believe they are more due to realism for the 1965's audience, than else.