Henry Louis Gates Jr. discovers that he's related to a medieval Irish warlord; Peter Gomes learns that his paternal ancestry descends from a Portuguese Jew, who fled his homeland to escape the Inquisition in the early 1500s.
Information about Morgan Freeman's great-grandmother is unearthed in the records of the Works Progress Administration, a Depression-era federal agency. Also: the story of theologian Peter Gomes' ancestors, who were freed in the late 1700s by Quakers.
The story of Chris Rock's great-great-grandfather, who served in South Carolina's state legislature following the Civil War. Also, Don Cheadle learns that his ancestors were enslaved by Chickasaw Indians.
An investigation of Tom Joyner's family history uncovers great-uncles who may have been unjustly executed. Also featured: author Bliss Broyard ("One Drop: My Father's Hidden Life"), whose black father passed as white.