BLYTHE Duff’s connection to royalty is incontestable. The actor was involved with the Prince’s Trust for years. She spent dinner time with King Charles (“I probably chewed his ear off all night”) became engaged on the Royal Yacht and, to crown it all, the Queen Mother was said to have ordered up Taggart tapes for a special royal binge watch.

So of course, Duff was affected by the recent death of Queen Elizabeth.

Yet, she says with a considered smile; “If you were ever going to do a play about the monarchy it could never have landed at a better time.”

Duff is speaking of her upcoming role in James IV, the latest of the dynamic plays by Rona Munro which charts the story of Scotland’s regal legacy via the James kings.

“Whether you are a monarchist or not you have to appreciate that the Queen gave an incredible service, and it has to be marked. But the passing of the Queen has focused the country on the history of the royal family in an unimaginable way.

“I was looking up at the buses in Edinburgh recently when the Queen died, and these huge James IV posters were plastered on. And it did make me think about the hearse actually passing these buses. It was quite a moment. And then you come to realise that James IV was the Queen’s great-great grandfather 12 times removed.”

She adds: “Scots know about Mary Queen of Scots, but that’s about it. The audiences didn’t really know a lot about the reigns of James 1, 2 and 3. Now, in James 1V we come to learn this is a key point in history. What Rona does really well is fill in the gaps in that period in history.”

The previous James plays have proved to be both a massive success with critics and audiences, Munro revealing the deftest of touches in bringing together drama and education with humour and poignant storytelling.

Blythe Duff didn’t study Scottish history in school growing up in East Kilbride – (“I remember we studied crop rotation, the 1845 period and the agrarian revolution up until World War One”) – it seems few of her generation did. But since becoming involved in the James Plays the actor has wallowed in learning of the connectivity, how themes often repeat themselves.

She has become fascinated in learning of vying for power, double dealing, duplicity, great rivalries and secret affairs.

This latest play reveals all of that, and much more. James Stewart, Duke of Rothesay, became James IV after his father, James III, was killed – or – murdered during or after the Battle of Sauchieburn in 1488.

James IV was just 15 when he took part in the rebellion that led to his father’s death, and for the remaining 25 years of his life, he did penance for his patricidal and regicidal actions, wearing a heavy metal belt around his waist, adding weight with each passing year.

He married a 13-year-old, and had a series of illegitimate children, as was very much the norm for the period.

And while his father James III was about cultural development, James IV carries this forward. Often remembered as Scotland’s ‘Renaissance King’, he was a patron of the arts and sciences and who was keen to showcase the royal family with his touring pageants. We had a modernising Scotland, keen to stand out in Europe, yet a country which was clearing the Highlands.

Rona Munro brings, as would be expected, a fresh take on the telling of this period. Scotland in 1504 is seen through the eyes of new arrivals Ellen and Anne, two Moorish women who were expected to take their place at a royal court.... but not this one.

“The play starts with the capture of a ship on its way to England containing these Moorish attendants who are brought into court,” explains Duff. “They are elevated in order that England and Italy and France would see these exotic souls around us.”

The story of the Moorish attendants is not simply a theatrical device to allow for outsiders offering a view of the goings-on in royal Scotland. “It’s accurate. Rona has discovered there were Moorish attendants in the court, who were almost royalty and very well versed.”

In the previous plays, Duff has played characters who were fundamentally dark. “This time around my character, Dame Phemy, is fundamentally evil,” says the actor, clearly relishing the opportunity to play a character on the extremes of human behaviour. “She’s absolutely vile. She’s been around the court for the longest time, she has to look after people, keep people fed, spinning all the plates and every time we see her, she seems to be next to the king.

“Phemy also has a tremendous power; for example, she gets to decide when the king will be received into the Queen’s boudoir. So, she’s a challenge to play. You have to find a way in which she can rationalise her arguments to herself at least. She has to have some logic for saying the vile things she does and, as time goes on, I’m coming to realise the depths she has to deal with.”

The language of the play has been challenging. It will sound racist in parts. “How we spoke of people from other countries, how we dealt with them, was so very different. Yes, it was meant to be racist, and thankfully we’ve come a long way since.”

Rona doesn’t sugar coat royalty in this play, produced by the National Theatre of Scotland. “She tells it warts and all. But she really helped me understand why we honour the monarchy in the way we do now.”

The actor said after the last James play that her working life felt complete. And the work was "exhausting".

At 60, is James IV her swansong? “That’s the question my husband keeps asking,” she says, grinning. “He’s retired and thinks it would be nice if we both were.”

But she’s an actor. Actors don’t leave the stage. Especially when they’re involved in a great production. “You’re right. But don’t tell my husband I said that.”

The world premiere of James IV: Queen of the Fight debuts at the Festival Theatre, Edinburgh from September 30 and tours Scotland, including the Theatre Royal, Glasgow, October 11-15.