Plot summary

A flying saucer orbits 1950s Earth and lands in Washington, DC, on the Mall. The lone live occupant, stepping out, is shot by a jumpy soldier. Gort, a large and very powerful robot, appears to save him, melting tanks and guns with just a slight bit of its power. The wounded alien, ordering Gort to stop his rampage, is taken to a hospital from which he recovers and escapes in order to learn more about this planet, even moving in as a boarder alongside an Earth family. When the family begin to suspect him, he reveals himself, along with the news that Gort is a member of a race of super-robot peace enforcers that will destroy the Earth if provoked.—John Vogel