A gruelling watch, but one of Bergman's finest films. Interesting to compare this with The Hour of the Wolf, as both feature the same lead actors as artists (or an artist and his wife) who have taken sanctuary on an island. In the earlier film it's largely inner demons that lead to von Sydows disintegrating personality (at least that's how I read it) whereas here it's very much circumstances beyond his control.
Much has been written about the unsympathetic central characters, particularly von Sydow's. For me there are flashes of a good (if flawed) man early in the film, but one who copes badly with adversity. The flaws become all that is left as his humanity is gradually eroded by one horror after another.
I watched A Passion (Ullmann and von Sydow on their island again) soon after this, and was amazed to recognise many of the same locations. And then there's a dream sequence...
