Who Do You Think You Are?

Singer Kelly Clarkson explores her lineage and uncovers an ancestor deeply rooted in American history. Coming face-to-face with her three-times great-grandfather's wartime bravery and sacrifice, she finds a connection deeper than ever imagined.

Actress Christina Applegate investigates her paternal grandmother -- the woman who disappeared from her father's life when he was very young. Christina gains insight into the life and hardships of the woman she and her father loved, but never knew.

Media mogul Chelsea Handler confronts a deep family secret: her grandfather's rumored Nazi past. As she dives into her family's struggle to survive in a desperate time, the uncovered details finally confirm or deny his affiliation to the dark regime.

Actress Zooey Deschanel searches for rumored abolitionists in her father's Quaker family background. Her journey takes her around Pennsylvania where she uncovers, and follows, the story of a remarkable ancestor who sacrificed everything for her beliefs.

In memory of his late father, actor Chris O'Donnell investigates the paternal side of his family and finds ancestors on the front lines of American history. Chris explores a patriotic legacy and a family devotion that extends deeper than he ever imagined.

Supermodel Cindy Crawford travels to the United Kingdom and Germany and discovers ancestors dating back to the English Civil War. She even finds a connection linking her to early European royalty.

Country singer Trisha Yearwood knows little about the paternal side of her family since her parents passed. Searching for a deeper family connection, Trisha travels to England and uncovers an ancestor's history of crime, loss and perseverance.

In tribute to his late father, actor Jim Parsons explores the ancestors on his paternal side of the family. He follows clues to Louisiana and eventually France, where he discovers generations of his forefathers who made an indelible mark on history.