The Day The Earth Stood Still (1951) (DVD) (Second-Hand)

A Spacecraft, lands in Washington, D.C. and an alien emerges, flanked by a menacing robot with destructive capabilities far beyond anyone's imagination. So begins the science-fiction thriller, The Day the Earth Stood Still, a classic "atomic movie" from the '50s that would go on to inspire alien-invasion films for decades to come. Rebuffed in his efforts to meet the world's leaders and warn them of Earth's impending doom, the alien, Klaatu (Michael Rennie), takes to the streets. Klaatu's plea for peace is embraced by a pretty young woman (Patricia Neal) and an eminent scientist, (Sam Jaffe), but the rest of humanity reacts with mistrust, fear and violence. With time running out, Klaatu is forced to demonstrate his awesome powers in a mind-boggling display, teaching all of mankind a lesson for the ages.