It's over five hours long, it's in Swedish with English subtitles, it has no post-production visual effects or even any Steadicams. There's almost no music, and the sound is in mono. None of this matters. Seriously, this movie ranks with The Godfather or Barry Lyndon in terms of sheer excellence.
I don't really want to say much of what it's about, except that there's a family that owns a theater in Sweden in the early twentieth century, and starting with their Christmas dinner one year a lot of things happen, some but not all of which involve the supernatural. Not knowing what's going to happen in the movie is part of the fun. (By the way, try not to read too many online reviews, as most of them just say that yes, the movie's genius, and then go on to a spoiler-filled plot summary.)
It's 312 minutes, and the director (Ingmar Bergman) insists that you watch it in one day, but there are three breaks for intermission, so that's not so hard. There's some comedy, some tragedy, some romance, some horror, and some fantasy, and near the end it turns to a meditation on philosophy and theology that's completely mindblowing. There is a three-hour theatrical cut as well that ended up winning four Oscars, but don't be a wuss--you have to get the five-hour cut and go for the full ride.
(For those of you who are Bergman fans--the thing I've never liked about many of his movies, as good as they are, is that watching them is work. His movies tend to be grim and unforgiving (especially Cries and Whispers, which I don't think I can ever make myself watch again, even though it was brilliant). But this movie's fun, even though there's a strong sense of melancholy in some parts. Maybe it's because the main character is a ten-year-old boy, but there's a sense of playfulness to the whole thing that makes all the philosophy and theology more interesting, without watering it down.)
What a great movie. If it weren't so freakin' long I'd watch it again tomorrow.