After a flying saucer lands in the National Mall in Washington, D.C., the United States Army quickly surrounds it with soldiers and tanks. A humanoid in a spacesuit emerges, announcing that he comes “in peace and with good will”. While the alien is opening a small metallic device, he is shot and wounded by a nervous soldier. A large robot emerges from the saucer and quickly disintegrates the soldiers’ weapons, including tanks. The alien, Klaatu, orders the robot, Gort, to desist.
The moral of the story is later revealed as Klaatu concludes, “Your choice is simple: join us and live in peace, or pursue your present course and face obliteration.”