Klaatu Barada Nikto!!!

Klaatu (Michael Rennie) is a representative of an alien race, most likely Martians, who are fearful of Earth's messing around with nuclear power. He has been sent in his flying saucer to warn earthlings that, unless they curb their violent tendencies and get along, they will all be destroyed in order to protect the rest of the universe. Of course, as soon as he steps off his ship, the army shoots him, locks him up in a hospital, and refuses to allow him to speak to representatives from other nations. He is forced to escape, leaving his ship guarded by the robot Gort, who demonstrates his power by disintegrating several tanks.

Klaatu decides to live among humans for a while, which is easy, since he looks a little like Kirk Douglas. He moves into a boarding house inhabited by Bobby (Billy Gray), the only human he meets who isn't completely terrified by the thought of aliens. Bobby thinks the idea is kinda cool. Bobby shows him around Washington, allowing him some meaningful moments at the Lincoln memorial, where Klaatu wonders why there aren't more people around like him. Meanwhile, Klaatu wants to meet the smartest guy in the world, one Professor Barnhardt (Sam Jaffe), and explain to him what the government stooges won't listen to.

The film shows a naive understanding of the so-called honorable science community, as if they were driven by a greater good than ordinary people. These scientists were the ones who developed the nuclear power the aliens feared so much, and I doubt they are more moral or conscientious than anyone else. However, it's from a time when people were more innocent about such things. The movie is naive, yes, but in a refreshing, pure way, made by people who still thought that the future wasn't completely bleak, and that maybe art could do something to help.