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The Day The Earth Stood Still (1951) was a brilliant science-fiction film that set the standards, in many ways, for other following films.  One of the great strengths of the genre of science-fiction as well as horror and fantasy is its ability to comment on direct issues in contemporary society.  In this 20th Century Fox film, the director, Robert Wise uses the arrival of an alien spaceship on earth as a cautionary message about the potential of the human race to cause its own self-destruction through atomic warfare.

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The core plot element is that beings from advanced civilizations on other planets have found people on earth have developed both nuclear weapons and a space program. They have sent an emissary, Klaatu, played by Michael Rennie, to deliver a gift and a warning to the people of Earth.  The gift, a small box, was destroyed by a frightened soldier…