My Family, The Holocaust and Me participants describe "enormous privilege" of taking part

And while acknowledging the harrowing nature of some of the revelations, many of those who took part have said that it was a hugely rewarding experience.

Emmerdale actor Louisa Clein, who appears alongside her sister Natalie, spoke of the "enormous privilege" of taking part.

Speaking to RadioTimes.com and other press about retracing her grandparents' steps, she said: "We went at one point into a tiny little room at the top of a house where my grandfather was hidden for a while, and I looked out of the window and I thought, 'This is the view that he saw.'

"I found it extremely moving to look out of a window and know it was the same view. The trees might be a little bit taller now but it's the same view that my grandparents will have seen.

She added: "There's a lot that my sister and I discovered that didn't actually make it into the final edit. It was just the most extraordinary gift to be able to meet these people who knew our mother, and knew my grandparents."

Holocaust educator Noemie Lopian, whose parents were both Holocaust survivors, echoed those sentiments, saying: "I'm extremely glad I took part in the programme, I learned so much about my mother, about my mother's family and about my people."

She said that visiting the prison where her mother was held by Nazis in Annemasse, France, near the Swiss border, was particularly powerful.

"I thought I was steeped in the Holocaust, but to actually relive, particularly the scene in the prison, to feel it and to relive it gives an extra dimension and it's taught me something powerful – that as survivors get older and fewer these sites will be of increasing importance to relive and to see."

And Angela Cohen – Robert Rinder's mother – said that while the programme was difficult she was also glad to have taken part. "I can't thank [directors] David Vincent and Mike Roberts enough for giving me the opportunity to go there.

"My father didn't talk about anything that had happened to him, I didn't even know the name of his brother and sisters. And sometimes my father sits on my shoulder and I just know he's with me and I just know he must have been so pleased that I stood there."

Meanwhile, another participant, Bernie Graham, said that while the programme had a huge impact on him, he struggled to find the right words to sum up his experience.

"I've got more detail, and context around the holocaust, but I struggle to say I was 'glad' to take part, I'm looking for a different word," he said.

"I also struggled when I went to Dachau when the PR man came up to me and said 'welcome to Dachau', I couldn't put those two words together either. So yes it has had an impact, I would do it again, I think it was of benefit to do it, but I can't use the word 'pleased'."

My Family, The Holocaust and Me begins on Monday 9th November on BBC One. Looking for something else to watch? Check out our TV Guide.