How we make Who Do You Think You Are?

Celebrity + history = TV gold. That’s the formula BBC bosses are celebrating as they toast the 20th anniversary of their star-spangled genealogy series Who Do You Think You Are? . It’s a series that has flipped identities on their heads: East End geezer-actor Danny Dyer found out he had a royal pedigree and British-Jamaican chef Ainsley Harriott discovered his great-grandfather wasn’t a black slave but a white slave owner.

During culture wars that have people hunkering belligerently into their bubble-bunkers, the show has continued to offer a gentle, human reminder that most of us have connections to groups against whom we may have defined ourselves. “We don’t shy away from difficult history,” says Lucy Swingler, the history documentary-maker who has produced the new series. She notes that at a time when Britain has experienced rioting over immigration, the programme has reminded us that some of our most beloved national treasures have foreign heritage.

She points out that Who Do You Think You Are? found that even the “quintessentially English” actress Olivia Colman had an Indian ancestor, “highlighting the diversity of the family threads that run through us all.” Respectful but unswerving, this new series clambers up the family trees of actresses Vicky McClure and Rose Ayling-Ellis; comic Paddy McGuinness, pop stars Olly Murs and Mel C; reality TV star Gemma Collins and retired athlete Dame Jessica Ennis-Hill. “The great thing about the show is that we�.