The Harvard scholar turns to the latest tools of genealogy and genetics to explore the family histories of 12 renowned Americans — professor and poet Elizabeth Alexander, chef Mario Batali, comedian Stephen Colbert, novelist Louise Erdrich, journalist Malcolm Gladwell, actress Eva Longoria, musician Yo-Yo Ma, director Mike Nichols, Her Majesty Queen Noor, television host / heart surgeon Dr. Mehmet Oz, actress Meryl Street, and figure skater Kristi Yamaguchi.