Monsters (2010)

Monsters is a 2010 post-apocalyptic horror/science fiction film, where a NASA probe has crashed in Mexico leading to the appearance of enormous alien creatures that are now spreading. This is a great entry into the monster movie category of the horror genre. Plex has links to where you can see it streaming.

trailer:

Roger Ebert's site gives it a positive review and says, "It's based on characters, relationships, fear and mostly unseen menace, and although the movie's special effects are important, it's not about special effects." The Guardian calls it "a thrilling postmodern sci-fi film". Empire Online closes a positive review by calling it "sci-fi filmmaking at its best."