AAAAHHHH!!!! Now I remember Kagemusha! That was a great ending! Totally forgot I saw that movie.
And I've heard of Stalker a few times. You mind going into more detail Morbii??
kawaiku,
Stalker is Andrei Tarkovsky's vision of the book "Roadside Picnic". From what I understand, it probably deviates from the book a bit (or even a lot). There was also a video game based on the book called S.T.A.L.K.E.R. that some people have talked about on this very forum. However, if you play that game, I would strongly suggest holding back from even considering the two might be similar (from what I know about the game, they are probably worlds apart - the only thing in common might be the setting).
Tarkovsky was a philospher and Russian Orthodox Christian. He had a lot of interesting things to say about film in general (he has a book that I've read - interesting and there are passages that can blow one away). Given some of what I've just said, the film itself is DEFINITELY a thinking man's film. I personally find it to be about belief on the whole, but there is probably MUCH more to it than that.
Tarkovsky also felt (and this is sort of a paraphrase and what I recall from what I've read) that a great film will live in a genre but show no "signs" of that genre. Stalker is that film (I remember reading that he thought Solaris [another great film] had failed because it was a sci-fi film that had several elements of sci-fi). Stalker is a sci-fi film, but you won't really find anything in the film that has elements of sci-fi, except maybe the story/dialogue itself (e.g. there aren't laser blasters, high tech, etc).
You can probably do a lot better than read what I'm saying - I'd bet a google search will probably yield far more encouraging words for the film.