When an enigmatic monolith is found buried on the moon, scientists are amazed to discover that it's at least 3 million years old. Even more amazing, after it's unearthed the artifact releases a powerful signal aimed at Saturn. What sort of alarm has been triggered? To find out, a manned spacecraft, the Discovery, is sent to investigate. Its crew is highly trained--the best--and they are assisted by a self-aware computer, the ultra-capable HAL 9000....