When a UFO lands in Washington, DC, bearing a message for Earth's leaders, all of humanity stands still. Klaatu has come on behalf of alien life who have been watching Cold War-era nuclear proliferation on Earth. However, it is Klaatu's soft-spoken robot Gort that presents a more immediate threat to onlookers. A single mother and her son teach the world about peace and tolerance, ousting the tanks and soldiers that greet the alien's arrival.