I had seen it a couple of times already but my last watching was a long time ago.
This is really a masterpiece. I'm always caught in this movie and amazed by its atmosphere, story, themes, every time I watch it, almost like the first time I discovered it.
It really is great : great actors (Natalie Portman, Hugo Weaving, Stephen Rea most notably), great story, great atmosphere (the visuals are particular but really impressive to me, it gives the movie some really original ambiance), and great scenes (a lot of them are memorable).
The movie makes you wonder and think about a lot of important themes, and it really is a beautiful story. The fact that the hero never shows his face and that we always see him with a mask is a big achievement in terms of story-telling too. Also, it's really a character that you love and hate at the same time.
I can only advise you to watch it if you've never seen it!