The Day the Earth Stood Still (1951)

Description   [from Freebase]

The Day the Earth Stood Still is a 1951 American science fiction film directed by Robert Wise. It was written by Edmund H. North, based on the short story "Farewell to the Master" (1940) by Harry Bates. The film stars Michael Rennie, Patricia Neal, Sam Jaffe, and Hugh Marlowe. In the film, a humanoid alien visitor comes to Earth, accompanied by a powerful robot, to issue an ultimatum to humanity. An extraterrestrial flying saucer is tracked flying around the Earth until it lands on the President's Park Ellipse in Washington, D.C.. Klaatu (Michael Rennie) emerges, announcing that he has come from outer space on a goodwill mission. When he takes out and opens a small device, Klaatu is shot and wounded by a nervous soldier. In response, Gort, a large humanoid robot, emerges from the ship and begins disintegrating the weapons present with a ray coming from a visor like structure on its head. Gort continues until Klaatu orders him to stop. Klaatu explains that the now destroyed object was a viewing device, a gift for the President. Klaatu is taken to an army hospital, where he is found to be physically human, but stuns the doctors with the quickness of his healing.

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