A lot of credit has to be given when a film is carried so well by a single actor. There's not a dull moment to be found in MOON, despite the fact that it is a somewhat bleak film set in space, and despite the fact that the screen is dominated by a lone performer, Sam Rockwell (who plays two "versions" of his character in the movie, but further explaining that would force me to move into spoiler territory). Those who don't like "space movies" may be turned off by the poster for MOON, but the poster is actually deceptive because MOON isn't exactly what you'd call a "space movie," since most of its scenes occur inside the base where our main character is located. While this movie is a little simpler than I would've liked it to be (given the deep subject matter), it still mostly succeeds at what it tries to do.
One of the most interesting aspects of this film is that it gives us the opportunity to make a comparison between how a human being behaves when he is only just starting an arduous venture (a 3-year odyssey in space, in this case) and the state he's in once he's nearing the end of it. Rockwell has the difficult task of embodying both of these personas, and while he's more successful at portraying the latter one (which is surprising, because you'd expect it'd be harder to play a demoralized and worn-out person than to play a physically strong and enthusiastic one), his work is still 100% solid throughout the entire film. The movie also benefits from an intelligent and often witty script ("You look like a radioactive tampon!"), which is so often lacking in so many of the dense and lackluster films that make up this genre.
The other noteworthy subject is MOON's stance on the concept of cloning, and the way in which it gets across its criticism. As I said, going too deep into this would force me to spoil things, but what needs to be said is that, while the film deals with this topic intelligently (for the most part), with a few twists and turns thrown in for good measure, its final moments portray the film's stance a little too obviously, from our protagonist's statement of "We're not programmed, we're people," to the final comments we hear from people on the radio right before credits roll.
If there's one aspect of MOON that is great, it's the pulsating piano-based score that is used during the film's more tense moments. The score during the lighter moments is a bit too "pretty" and conventional for my taste, and doesn't seem to fit the setting all that well either, but the score that is used for the tenser moments is magnificent. Despite the genre, the film doesn't have many explosions or moments in which eye-popping special effects are employed, but that makes sense, because this is more of a pensive cinematic piece, which is something I welcome heartily. With his role in the recent CHOKE, and now his doubly strong performance in MOON, Sam Rockwell has totally established himself as an actor to watch, and once he stars in something more Oscar-baity, there's no doubt that he'll have a strong chance at recognition.