To 120 million fans in 250 territories around the world it will always be Downton Abbey - home to the Crawleys. But to Fiona, the 8th Countess of Carnarvon, Hampshire’s Highclere Castle really is home.
Here, she reveals to The Mirror what allowing the cast and crew of Downton Abbey - first screened by ITV in 2010 and the subject of three movies - to take over her castle was really like.
Speaking ahead of the release of the third and final movie - Downton Abbey: The Grand Finale - on September 13, she says: "I soon learned all the actors spent much of their time in hairnets and curlers, endlessly waiting.
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“Jim Carter, as butler Mr Carson, sometimes had to wait all day just to open the dining-room door and say, 'Dinner is served, Milady.’”
Lady Fiona, 61, whose book A Year at Highclere: Secrets and Stories from The Real Downton Abbey is published on Thursday (September 4), moved into the castle with husband George, 68, the 8th Earl, after his father’s death in 2001. It has been the family seat of the Earls of Carnarvon since 1679.
Recalling the first day of filming in March 2010, Lady Carnarvon writes: "Our photographs had disappeared into cupboards and drawers, whilst those of strangers took their place - the as yet unknown Lord Grantham (Hugh Bonneville) and family now appeared in ornate frames on various tables and desks.
"A green lacquered antique box was sitting in its usual place on top of the table opposite the fireplace. Geordie asked: "Should we leave this here? Do you think? Is it safe?"
"Unfortunately, by the end of the very first day, a lighting boom dropped precisely on the green box I had said would be fine. The Downton crew were mortified."
And she recalls giving a crew member - speeding through the front call with a long pole balanced on his shoulder - a ticking off, after a near collision with a Van Dyck painting.
She writes: "I said, ‘Excuse me. Could you go a little slower and more carefully? You nearly hit the painting!’ He said ‘All right, love. A Van Gogh, is it?’ I said ‘No, it's a Van Dyck actually?’”
After that near disaster, much of the crockery and glassware was rented for use on set, while their “Meissen, the Chinese vases and Napoleon's desk,” were locked away safely.
Usually sharing their home with their eight dogs, life with the Downton entourage took some adjustment. Lady Carnarvon writes: "There would be about 120 crew on-site, all arriving for a 7am start.

"Polished black cars would bring the 'talent' in from the main drive. Actors would emerge swathed in huge black puffer coats with hair in curlers and Ugg boots on their feet, phones to hand and make-up experts trailing behind.”
And while viewers lapped up scenes of lavish dinners, the food was fake and Lady Carnarvon says the filming was laborious.
She writes: “A dining scene always took an 11-hour day to film. Most filming days seemed to be either about eating or waiting, which suited our Labradors.
"During one tea scene that was being filmed, Alfie (the Labrador) managed to sneak on-set and sample a little cake, which was on the table opposite the fireplace in the saloon. However, as the cast never really ate on-set but just pretended, I smoothed it down with a knife and turned it round, so I don't think they noticed."
In the final movie, audiences will see the Crawley family getting to grips with "modern life" as they enter the 1930s and facing financial difficulties, resulting from the Great Depression.
Fans will be delighted to see most of the show's main cast returning - including Hugh Bonneville as Lord Grantham, Laura Carmichael as Lady Edith Pelham, Jim Carter as former butler Charles Carson and Michelle Dockery as Lady Mary Crawley.
But Lady Carnarvon says she will miss Dame Maggie Smith, who died in September 2024, aged 89. "Downton had many stars, but undoubtedly Dame Maggie Smith shone the brightest," she recalls.
"I remember her saying on The Graham Norton Show, ‘I led a perfectly normal life until Downton Abbey. I'm not kidding?’ The razzmatazz and red carpet parts of show business were not for her.
"When she first started filming at Highclere she did have her own room. In the winter, because she liked privacy, we offered Dame Maggie a sitting room to use and our housekeeper would bring her tea.
"I rarely saw her clutching a script, but her skill as an actress could be seen in the way she threw away some lines or would turn to look at another actor, holding a moment of silence."
Lady Carnarvon does recall one incident that left Dame Maggie decidedly unamused. She recalls: "One morning the (fire) alarm went off and we evacuated the castle. Having identified the fault caused by a carpet being fitted, one of our staff was under pressure to let the cast back in to resume filming.
"The fire brigade arrived and the senior fire officer was not amused. Our staff member was reprimanded and asked to evacuate again. As Maggie Smith came out, she made her evident disapproval known with quelling looks."
Another enigmatic star was Shirley MacLaine, the Hollywood legend who joined the third and fourth Downton TV series as brash Martha Levinson, mother of Cora, Countess of Grantham - played by Elizabeth McGovern.
Highclere staff were stunned when MacLaine - who has written books on reincarnation - claimed to be related to Egyptian royalty.
Lady Carnarvon, who recalls in her book how the 5th Earl of Carnarvon provided the financial backing for Howard Carter's excavation that led to the discovery of King Tutankhamun's tomb in the Valley of the Kings in 1922, writes: "Undeniably Hollywood royalty, Shirley explained she was the reincarnation of an Egyptian princess. A formidable lady, it was far better to nod in agreement, as she was in no doubt about this.
"She was also convinced that her beloved little dog, a terrier called Terry, who went everywhere with her, was a reincarnation of the jackal-headed Egyptian god Anubis. She later said of Highclere, ‘They had the tomb of King Tut in the basement.’”
“She said that the castle was haunted and pictures came off the wall, which I had not noticed, although, given we also had Professor Minerva McGonagall (Dame Maggie) from Harry Potter upstairs, it might just possibly have been true."
Another memorable time was when George Clooney filmed a special ITV charity edition of Downton in 2014. Lady Carnarvon writes: "Downton reignited ITV's reputation and its advertising revenues. So, in the summer of 2014, ITV filmed a Text Santa skit which involved George arriving at Highclere.
"I sincerely believe that most women who worked at ITV came to Highclere that day. So did the press, but only as far as our gates, as they thought Mr Clooney might be considering Highclere as a venue for his wedding to then fiancée Amal Alamuddin.
"At the height of Downton, there were paparazzi looking for behind-the-scenes photos all over the place, and much excitement when one photographer was found in the azalea bushes wearing a balaclava."
Lady Carnarvon admits she will miss the Downton film crews. "We are so grateful to have been part of the journey. The phrase ‘Downton Abbey’ has now passed into everyday language; things or events are described as ‘very Downton’.
"I'm still not sure what caused it to become such a global success. Perhaps it was the fact that there are not many programmes to watch on TV that do not involve or focus on violence or death Instead, Downton highlighted conversation and family stories.”

And as the curtain rises on the new and final film, she adds: "Despite all the long days and the challenges, the final ‘It's in the can’ was a moment of both elation and of sadness. When we part company none of us ever knows whether we will get the call again. It's a wrap."
*A Year at Highclere: Secrets and Stories from The Real Downton Abbey, by The Countess of Carnarvon, is published on September 4 by Century priced £22. Downton Abbey: The Grand Finale is in cinemas from September 12.
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