Who Do You Think You Are?

BBC1, Monday, 9pm ****

IN Harry Hill’s Alien Fun Capsule at the weekend, the big collared one described the genealogy show Who Do You Think You Are as the programme in which “well known people cry over people they’ve never even heard of who died hundreds of years ago”.

If that was so, the first in the new series conformed to type. Daniel Radcliffe, Harry Potter as was, cried not once but twice and it was touch and go at other times. So far, so predictable. Yet Radcliffe’s story turned out to have twists and turns his literary mucker JK Rowling would have envied, so out of a clear blue sky did they appear.

Who Do You Think You Are, now in its 16th series, is at its best at such times, when the viewer reckons they have a handle on the subject but it turns out they do not. Who would have thought, for example, that Jeremy Paxman’s great great grandmother had been a Glaswegian widow living in such poverty with her nine children that it would make the normally clear-eyed journalist weep?

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With his casting director mother, literary agent father, and west London childhood, Radcliffe’s story appeared as if it would be straightforward enough. Perhaps a bohemian twist or two lay in store, connections to someone famous in the theatre.

The first sign of something more complex was a name change on his great grandmother’s side, from Gershon to Gresham. While this could have been a way of anglicising a Jewish surname, not unheard of at the time, Radcliffe, with the help of experts, dug deeper.

He had known about a great grandfather who was a diamond merchant in Hatton Garden, and that his life had ended tragically. It did not take too much digging to uncover the facts. While doing so, Radcliffe was also given a picture of the Britain of the 1930s, a grim place riddled with anti-Semitism.

Radcliffe, now 29, was handed the last thing his great grandfather had written, a letter to his wife, Rachel. He was in tears before the first paragraph had ended, and he was not alone. “It is so funny to feel this connection to someone you don’t know,” he said. And he did feel a bond. There were phrases here that he used, similar endearments he deployed. Coincidence, chance, or something more mysterious?

There was another sad story, this one was a more commonplace tragedy, the loss of a young man in the First World War. The soldier’s letters home had survived, and extremely moving they were, too. Even though the various genealogists and historians kept making him cry, Radcliffe was the very model of politeness and gratitude. He had seemed like a nice kid in all those films and interviews, and what do you know, he was.

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In the end, the most remarkable thing in Radcliffe’s history turned out not to be the hellish trenches or Hatton Garden, but what happened after his great grandfather’s death. His wife put one foot in front of the other and lived on. She endured. She changed her name to distance herself from the scandal, and brought her children up alone. She was the author of her own happy ending.

“As much as this is about the tragedy and extreme fallibility of one of my male ancestors,” said Radcliffe, “it is also the story of the triumph of all the women that followed him.” Whatever else he got from the Who Do You Think You Are experience, Radcliffe had certainly acquired a new heroine.

Available on iPlayer