Dame Judi Dench is related to Scandinavian royals

She reflected: "I had no idea about any of that. Or even that we had any Danish connections but this I have found out is my mother's family and now of course I want to explore it further.

"And now I believe there are Swedish connections too, this may well prompt a visit there as well!"

During the episode, Judi also explained why she was so determined to appear on the BBC series, admitting that her mother was a driving force behind the decision.

The acclaimed actress - who has enjoyed success on stage and on the big screen - shared: "Not knowing anything about my mother's side of the family I was very interested to find out more. I know that we have the head of a unicorn as our family crest and I was very interested to find out whether it had a motto below it.

"In the course of the programme, I found out about two family mottos but I'm not sure if one of them goes with the unicorn crest. I would like to find that out."

Asked if she was worried about discovering any potentially unwelcome surprises on the show, Judi replied: "I am sure that investigating anyone's past would have parts that could surprise or even shock you.

"The work that researchers do is so thorough that there are bound to be some surprises to be found. Naturally, I was concerned about the possibility of what I might be told."