An odd one: circular, elliptical structure, minimal dialogue, annoying framing device (not a narrative one, but a literal one; it has rounded corners, as though you're watching a movie on one of those old GAF View Master toys).
It's not giving much away to inform you that the guy dies in the first 10 minutes of the movie, after which he appears to fail to take the proper course to the afterlife or whatever and instead hangs around his house being sad in a bed sheet (which is initially extremely distracting and ridiculous, but you gradually become accustomed to it). He seems to become unstuck in time, yet rooted to the same physical location. There are some really, really long, static shots, which I guess serve to underscore how the ghost has an eternity of time to fill and nothing to do except be sad about how he's not with his wife anymore and it's actually quite poignant in that regard.
So it's kind of a meditation on death and loss from a supernatural, but rarely-to-never traditionally "scary" perspective; a romantic, metaphysical exploration of separation with some gorgeous cinematography, but which requires no small amount of patience. It's nothing if not unique - I really can't think of anything to compare it to.