Moon (2009)

Moon is a 2009 sci-fi film about a a solitary lunar employee who experiences a personal crisis as the end of his three-year stint nears. It is the debut film of director Duncan Jones, a gripping and inspired movie. Sam Rockwell stars as the employee and Kevin Spacey voices his robot companion. Rockwell's acting is tremendous in the role of Sam Bell; he doesn't just carry the film - Moon is almost a one-man show and Rockwell conducts a master class.

The music composed by the brilliant Clint Mansell is out of this world. After the amazing "Requiem for a Dream" and "The Fountain", this one is at the same level. Especially the first and last tracks are awesome!
Check the comments to listen before you buy.

Overall, a thoughtful and extremely claustrophobic movie, that everyone must see. Definitely the best 2009 movie I've seen so far.

More Info:
Official Website
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Trailer: