Harvard scholar Henry Louis Gates, Jr. explores America's immigrant tapestry as he seeks answers to two simple questions: "What made America?" and "What makes us?" In this four-part series, Gates unravels the genealogy and genetics of 11 famous Americans, including: poet Elizabeth Alexander; chef Mario Batali; comedian Stephen Colbert; novelist Louise Erdrich; writer Malcolm Gladwell; cellist Yo-Yo Ma; film director Mike Nichols; Her Royal Highness Queen Noor; actress Eva Longoria; actress Meryl Streep; figure skater Kristi Yamaguchi; and TV personality Dr. Mehmet Oz. (Source: PBS)