September 20, 1862: In a bizarre twist of a genetic coil, Sam leaps into his great-grandfather, Captain John Beckett, during the Civil War. He must not interfere with his ancestor's romance with a riled southern belle named Olivia. He must also avoid being hanged as a Yankee dog by some home guard Confederate soldiers.

NOVA covers both sides of the stormy controversy over the Tasaday tribe. When these isolated cave dwellers were discovered in the Philippines in 1971, they were hailed as a Stone Age relic. Now, many anthropologists denounce them as fakes.