Nine celebrities trace their family trees to explore the lives of their ancestors and uncover major themes in British social history. Bruce Forsyth receives a letter from America from a woman who claims to be related to Bruce through Bruce's great-grandfather, Joseph Forsyth Johnson. The letter suggests that Joseph Forsyth Johnson was married to two women at the same time and that he died at sea. Bruce is determined to investigate these claims and discover the truth for himself. Bruce starts by visiting his cousin, Alan Johnson, who gives him a cache of family photographs and the diary of his great Aunt Christina, which he takes with him. Alan also gives him Joseph's business card - a vital aid for Bruce in tracking Joseph and his family's steps in the late 19th century. Bruce follows the business card to Bond Street, London, where Joseph opened a landscape gardening shop. Knowing that Joseph worked in America at some point, Bruce tracks down the passenger lists for Joseph's journey and is in for a shock. He heads off to New York on Joseph's trail, which then takes him to the American South. Bruce's quest to uncover his great grandfather's secret history ends back in New York where he finally discovers Joseph's fate. Joseph was a man who was both an extraordinary pioneer in his field; but also a man who bucked the social mores of the day and paid dearly for it, leaving a trail of confusion and unhappiness in his wake.