2001: A Space Odyssey

In an African desert millions of years ago, a tribe of hominids is driven away from its water hole by a rival tribe. They awaken to find a featureless black monolith has appeared before them. Influenced by the monolith, they discover how to use a bone as a weapon and drive their rivals away from the water hole.

Millions of years later, a Pan Am spaceplane carries Dr. Heywood Floyd to the huge Space Station V orbiting Earth for a layover on his trip to Clavius Base, a United States outpost on the Moon. After Floyd has a videophone call with his daughter, his Soviet scientist friend and her colleague ask about rumors of a mysterious epidemic at Clavius. Floyd declines to answer. At Clavius, Floyd heads a meeting of base personnel, apologizing for the epidemic cover story but stressing secrecy. His mission is to investigate a recently found artifact buried four million years ago. Floyd and others ride in a Moonbus to the artifact, a monolith identical to the one encountered by the ape-men. Sunlight strikes the monolith and a loud high-pitched radio signal is heard.