A flying saucer lands in Washington, D.C. with a humanoid extraterrestrial (Klaatu) and his protective robot (Gort) companion onboard. Klaatu has been sent to preach disarmament to all the world's leaders, but is told that assembling a meeting would be impossible (it's the height of the Cold War and the US-Eastern Bloc rivalry). Klaatu was sent because the residents of other planets have started fearing for their safety ever since the humans of Earth began harnessing atomic power. Klaatu escapes his confinement in a hospital and ventures into human society; society responds with a paranoid witch hunt. Since he can't get access to the world's leaders, he seeks out the smartest man he can find, the Einstein-esque Dr. Barnhart, and explains that his home planet has solved the problem of violence by creating a robot police force. He also tells Dr. Barnhart and his scientist friends that if humanity lets its violent nature bleed over into space exploration, Earth will be destroyed by the robots. His final words of warning: "The decision rests with you...."
In addition to being a sci fi classic, this movie is also a great time capsule of Cold War-era social commentary. It's not the subtlest or most exciting movie ever captured on film, but it showcases what so many sci fi stories try to achieve: we humans get in over our heads, and placing us in extraordinary circumstances is sometimes the only way to expose us to our own naivete.
