Veteran BBC news reporter and world affairs editor John Simpson always thought his great grandfather was Samuel F Cody, famous for being the first person to fly in Britain and a Wild West entertainer. It was only later that John discovered that his great grandmother, Lela King, had run off with Cody, taking her children with her. John follows the trail of his adventurous great grandmother and her life with Cody, the cowboy turned aviator. He also investigates what happened to the husband Lela left behind, John's real great grandfather, and makes a shocking discovery.

Nigel Havers takes a look at his mother's line and travels to Cornwall to learn about a tale of illegitimacy worthy of a period drama. On his father's side, he ends up in Colchester where he learns a tale of the Victorian equivalent of an Essex taxi driver made good, who ends up losing everything though.

Singer and '60s pop icon Marianne Faithfull had a difficult relationship with her mother, Eva. In this film Marianne investigates Eva's earlier life, as a dancer in 1920s Berlin- the era immortalised in the film Cabaret. Marianne also discovers her half-Jewish mother's precarious existence in Vienna during World War Two and investigates whether there is any truth in the rumour that the family was involved with the Austrian Resistance.

Hollywood actress Minnie Driver is on a mission to find out more about her late father, Ronnie, and his family's background. Minnie's parents were not married, and Minnie only discovered when she was older that her father had a wife and another family all the time Minnie's parents were together. Minnie knows her father was awarded a medal for his role in the battle of Heligoland Bight during World War Two, but is shocked to discover that he apparently threw it away. She sets out to investigate why her father would relinquish such an honour. The trail leads Minnie to relatives she never knew existed, and she discovers a kindred spirit in the family.

Comedian Sarah Millican is astonished to discover that her three times great grandfather was one of the first ever divers in the world. Sarah also follows the trail of her four times great grandfather, John Malcolm, to Canada where he worked for the Hudson's Bay Company. John was sent to a remote outpost involved in the fur trade. As Sarah follows in his footsteps, she makes a truly shocking discovery.

Actress Lesley Sharp was adopted when she was just five weeks old. She traced her birth mother over twenty years ago and discovered that she was the result of her mother's affair with a married man. Now, knowing that her biological father has passed away, Lesley is ready to find out more about him. She traces her half siblings and follows her paternal line back to discover that her great great grandfather fostered Barnardo's children. Lesley follows the trail of one of them, George Maybury, to Canada to meet George's grandson and to find out what kind of home her great great grandfather provided.

Sports presenter and former footballer Gary Lineker follows the trail of his great, great great grandfather James Pratt, and discovers that James was a poacher in Victorian England and served time in Leicester Prison. Gary wants to know why James ended up becoming a repeat offender. Gary also wants to get to the bottom of how his four times great grandfather Thomas Billingham, who was born to an illiterate gardener, ended up becoming a highly-skilled legal clerk.

Una Stubbs never got the chance to meet her paternal grandparents and learns that they didn't die until she was in her 20s. She manages to uncover a story of illegitimacy and poverty.

TV personality Nick Hewer has fond memories of his maternal Irish grandfather but has always been intrigued about how a Catholic managed to reach the prestigious office of high sheriff in Protestant-dominated 1920s Belfast. On his father's side, Nick goes further back - to his nine times great grandfather - and discovers how his family's fortunes were shaped by the English Civil War.

EastEnders star Nitin Ganatra moved to England from Kenya when he was just three years old. Now Nitin has questions about his identity and wants to investigate why his family left Kenya, and why they immigrated to Africa from India in the first place. The trail leads Nitin to Gujurat and his family's ancestral home. Along the way, Nitin makes an emotional and shocking discovery about his mother's family.