Who Do You Think You Are? - Season 4

Double-platinum singer Kelly Clarkson, explores her lineage and uncovers an ancestor deeply rooted in American history. Coming face-to-face with her 3x great grandfather's wartime bravery and sacrifice, she finds a connection deeper than ever imagined.

Actress Christina Applegate investigates her paternal grandmother - a stranger to her and her father. Uncovering dramatic details along the way, 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 details uncovered will finally confirm or deny his affiliation to the dark regime.

Actress Zooey Deschanel searches for rumored abolitionists in her father's Ouaker 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 frontlines of American history. Chris explores a patriotic legacy and a family devotion that extends deeper than he ever imagined.

World famous supermodel Cindy Crawford takes a journey to discover her family origins. With travels to the UK and beyond, she discovers ancestors dating back to the English Civil War, and even finds a connection linking her to early European royalty!

Since her parents passed, country singer Trisha Yearwood knows little about her paternal side of the family. Her search for a deeper family connection takes Trisha to England, where she 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. The journey takes Jim to Louisiana and eventually France, where he discovers generations of his forefathers who made an indelible mark in history.