The film is undeniably impressive from a technical standpoint, even though there isn’t much of a story to follow. *2001: A Space Odyssey* looks and sounds amazing; the visual and audio quality are truly remarkable considering it was made in 1968. To be honest, that's really the only reason I can give it a barely-passing grade. The plot itself left me feeling let down—it just doesn’t have much substance. It seems like the filmmakers were aiming for something artistic, which is obvious from the limited dialogue and lack of a straightforward narrative, along with all the ambiguity. It's a Stanley Kubrick film, although I haven't seen many of his movies; this is actually my first one, and that’s mostly based on what I’ve heard over the years. There are also quite a few long, drawn-out scenes that felt empty (presumably intentionally) and were distracting to me. It simply didn’t grab my attention, but I can still acknowledge its value. Because of all this, the actors feel pretty insignificant—and I realize that might sound harsh. Douglas Rain does fine work, and William Sylvester is acceptable too. I don't really fault the performers, since they aren't given much to do. Like a few other films I’ve seen, I’m happy to categorize this one as “I didn’t quite understand it, and that’s okay.” I’m still glad I watched it; I appreciate its technical aspects, and of course, I can see why others enjoy it so much.

Source on TMDB