The new Mayor of London, Boris Johnson, undertakes a surprising international investigation into his family roots, as the series continues.

Boris’s paternal grandparents had significant roles in his upbringing. He knows that his grandfather, “Johnny”, was the son of a Turkish journalist and politician who was ultimately kidnapped and lynched in the early Twenties. But, he knows little about his life, reputation and the circumstances of his death.

Boris’s half-French grandmother, “Granny Butter”, had always claimed to be of posh stock. Although suspicious of this claim, Boris and his siblings remember Granny Butter teaching them to eat crisps with a knife and fork.

Boris sets out to find out more about his roots in Turkey, and the experiences of his great-grandfather, whose vocations were so similar to his own. He encounters the ongoing effects of the political climate of his great-grandfather’s era in contemporary Turkey, and discovers personal details about his life and death. Returning to Western Europe, Boris sets off in search of the truth about Granny Butter’s background, and follows an intriguing family trail that reveals she was far, far posher than even she imagined.

The series continues with Jerry Springer, Esther Rantzen, David Suchet, Ainsley Harriott, Jodie Kidd and Laurence Llewelyn-Bowen.

Wednesday 20 August
9.00-10.00pm BBC ONE