Carol Vorderman grew up knowing very little about her absent father, but she believes she might find traits in his family that she recognises in herself. This really is a voyage into the unknown, where Carol hopes to unlock a hidden heritage - and understand more about her genetic inheritance.
Beginning on familiar ground, Carol investigates her maternal great grandfather, Daniel Davies, a butcher from North Wales, who once bought four houses from a bankrupt builder and gave them to his children. It was this kindness that ensured Carol inherited such a happy childhood home. Daniel also appears in a photograph outside an unknown building - along with someone who looks very like Queen Victoria.
A visit to Daniel's hometown of Prestatyn brings his character to life. Carol tracks down Daniel's shop, and meets an elderly resident who remembers its vibrant owner, and learns what a prosperous trade a local butcher would have done in this lively, expanding town. She even finds an advertisement for Daniel's shop in a tourist guide of 1913. No wonder he was wealthy enough to buy for houses for his children!
But what about Queen Victoria? The Times Digital Archive confirms that Queen Victoria did indeed visit Daniel's part of Wales in 1889 - but where was the photograph taken? It is a local resident who recognises Bodnant Hall - but, alas, Queen Victoria never went there! A local historian identifies 'Victoria' as Agnes, the wife of the gentleman who built it. But Carol admires David all the same: he was a businessman and an entrepreneur, who helped to make her childhood happy.
Turning to her paternal family, Carol travels to Holland, where her father grew up. She begins by investigating her great grandfather, Adolphe, who was supposed to have merited a Nobel Prize, but was denied it because he married an Indonesian lady.
Adolphe's marriage certificate soon disproves this tale, but, driven by her own passion for science, Carol visits the Eijkman Institute, named after the Nobel Prize winner, to ask the director whether her great grandfather really did deserve the Nobel Prize. She learns how his research into vitamins and a cure for Beri-Beri paved the way for Eijkman's prize - and Carol is rightly proud.
But what of Carol's father, Tony Vorderman? Carol had been told that her father was involved in the Dutch Resistance, and indeed there is a conspicuous gap in Tony's army record in the years after the German invasion.
Carol makes an appeal on television for information, and as a result meets one of her father's friends, in whose house Tony hid to avoid the German labour camps. She confirms that Tony possessed an illegal radio, and a visit to the local resistance museum reveals how members of the resistance listened to illegal broadcasts and distributed the information in pamphlets.
But it is documents in the local archives that further confirm the tale. Tony used to work at the Hotel Geisler - a centre of illegal pamphlet production. A police report of 1944 records an episode where Tony and 12 friends tried to cross the River Mann to freedom, but Tony triggered a landmine and was injured. Only one of the party won his freedom, and two of their number were killed.
Thus Carol understands why Tony never talked about the war. She wishes she had got to know him earlier. Indeed, she never had the chance to talk to him about it, as he died very shortly after the filming. But Carol has discovered a lot about her family, and also about herself. She now knows that her Welsh side is her nurtured side - and that the Dutch side is her nature.