Experiments with various acids and other substances failed. Still tinkering 15 years later, he set up a pewter plate layered with photosensitive bitumen of Judea on his attic window facing a courtyard ...

An alien (Klaatu) with his mighty robot (Gort) land their spacecraft on Cold War-era Earth just after the end of World War II. They bring an important message to the planet that Klaatu wishes to tell ...