WHO Do You Think You Are? has been one of the BBC’s true success stories of recent years.

Over 13 series and 10 international editions, the programme has sparked a huge interest in genealogy, with its clever mix of the emotional and historical and of course the promise that with a few clicks of a button you too could find something extraordinary lurking in an old census.

I’ll admit that it’s a show that I rarely miss and even when the personality in question is someone I really haven’t got much time for, it’s a programme that frequently delivers a poignant punch to the gut which is strangely satisfying. 

So far this series, which is three episodes old, hasn’t disappointed, with the opening edition concentrating on 70-year-old actor Charles Dance.

Given his recent role as Tywin Lannister in Game of Thrones, you’d think Dance would know a thing or two about dysfunctional families but what panned out was even stranger than fiction. 

Given his plummy tones it wouldn’t have been a surprise to find Dance uncovering some kind of royal connection but one of the delights of WDYTYA? is when apparent poshos find out their roots are for more humble than they thought.

Dance’s grandparents were a carpenter and a waitress but the drama really started with his parents and more specifically his father, who the actor had never really known, having been told he died when Dance was just four-years-old.

A military expert was quickly able to pinpoint when the uniform Dance senior was wearing in a photograph was worn and before you knew it, Dance junior was discovering he had a completely new family in South Africa, which included several great-great nephews who couldn’t believe their luck when a Game of Thrones star walked into their lives.

Moments later Dance is flicking through an autobiography written by the half-sister he never knew and he’s welling up in tears.

You’d be made of strong stuff not to be doing the same.