For Dame Helen Mirren, 2007 was undeniably her annus mirabilis. With her commanding portrayal of a beleaguered sovereign in The Queen, she swept all competition aside as she claimed acting award after acting award, finally crowning her achievement with an Oscar.
She had clearly shown that age was no barrier to getting meaty dramatic parts. So the scripts that rolled in afterwards must have made enticing reading.
So why exactly did she chose to play Nic Cage's mum in the fun but undeniably lightweight historical caper National Treasure 2: Book of Secrets?
A sequel to National Treasure, which had Cage hunting down the lost riches of the Founding Fathers, this time he is trying to clear his family's name after they are implicated in the assassination of Abraham Lincoln.
Dame Helen admits that when she first read the script that she suspected that, having just won the Oscar, she would be accused of selling out. And she didn't give two hoots.
"Yes!", she laughs. "Absolutely, really happily selling out."
At the time she hadn't seen the first film and sought it out to make sure that if she was going to make hokum, it was at least quality hokum.
"By the time the credits rolled I thought 'I am definitely going to do this'. It wasn't a great film but I loved the way it brought history to young people as an adventure, full of secrets, which it is.
"It was a fantastical Indiana Jones-style story but nevertheless used real history."
She was also rather impressed that the Americans weren't quite as precious about history as the British, possibly because we have more of it.
"It written by a team called the Wibberleys (Marianne and Cormac). They didn't write it the way Peter Morgan wrote The Queen.
"They plan the overall story but the individual precise historical things in it are heavily researched and academically correct within this fantastical thing. Which only the Americans would think of doing.
"Someone asked me how the Brits and the Americans think of history, and I don't think the British would throw all the toys out of the pram historically, the way National Treasure does. We'd go 'Oh you can't do that', whereas the Americans go 'Yes you can, it's fine'."
The story line has the stars searching for clues in desks in both Buckingham Palace and the Whitehouse. The actor Bruce Greenwood appears as the American President.
Unfortunately for Dame Helen she didn't get the opportunity to cameo in her most feted role.
"I did suggest it because they do go to Buckingham Palace, me just walking in the background. But they didn't go for it."
She suspects this might have been the closest she would get to playing that particular part again.
"The Queen was such an individual, idiosyncratic film, it was one of a kind. You can't repeat that. People have asked 'is there going to be a sequel?' Yes, let's do the Golden Jubilee. That would be interesting."
As compensation for being refused her in-joke bit part, she did get a rare chance to do some stunt work, action adventure having been, up until now, a genre she seemed to have overlooked in her otherwise impressive career in film, television and theatre.
"Swinging on wires, that was the best day of my life," she enthuses. "I have always wanted to fly and I have been in films where other people got to do it and I didn't.
"I am not the first Dame to be an action girl, I think that would be Diana Rigg."
In the spirit of movie-making comradeship, she also clambered into the hot tub with the crew, who were trying to warm up after spending hours submerged filming the climactic scene where heroes and villain are trapped by rising flood waters.
"I was in costume of course," she adds hastily. "I didn't take my clothes off because we were just permanently soaking wet."
It is this unpretentious earthiness that is part of Dame Helen's appeal. She remains a sex symbol at 62, cheerfully choosing outfits that emphasise the ample bosom she says is the reason she could never, despite her long-held desire to fly, play Peter Pan.
But at the same time she lacks that aura of high maintenance and ruthless willpower which you suspect is holding the likes of Sophia Loren and Raquel Welch together.
And though she is descended from Russian nobility - her real name is Ilyena Vasilievna Mironov - she is all grace and no airs. Though proud of her DBE she seldom uses the title.
"I don't insist on people using it. Maybe if I was Lady Helen I would. Dame makes you think of pantomime dames. Americans tend to think in terms of dames like Guys and Dolls."
It was while making National Treasure that she was invited to dine with the woman responsible, albeit indirectly, for her Oscar win.
Senior courtiers, it was alleged, were aghast at what they saw as a snub to the Queen, but Dame Helen maintains that her duty to her coworkers came first.
"I knew I had to be in south Dakota. I asked the producers how fixed the schedule was, because it was always changing and they said 'We're absolutely fixed. We have to be in south Dakota' "I couldn't say 'Do you mind if I took four days off?' because that's how long it would take to go to the function and come back. It was very tough.
"I hoped and assumed that hardworking professional people who commit to things and don't want to let people down would under-stand. They certainly said they did.
"I do wonder if I have blotted my copybook. I don't know."
The sequel reunites the stars of the original, with Dame Helen as the new girl joining their tight knit gang.
The fact that she was playing Nic Cage's mother wedded her, in the script at least, to Jon Voight as his father.
"I was very intimidated coming into this film because I'd never done a huge budget movie before and Jerry Bruckheimer (the producer) is like working for Emperor Hadrian. There's a massive reputation comes before him. Then there's Nicolas Cage and all the iconic films he has done. But they were so embracing and kind to me that they very quickly made me feel at home.
"Jon Voight and I, it was very strange. We're very different. We come from politically very different positions but we got on like a house on fire and I still don't know why.
"If he walked through the door right now we'd look at each other and start laughing because for some reason I make him laugh and he certainly makes me laugh.
"On our first day at Universal together we were so excited to find that we could go on the Universal Studios Tour for free that we both jumped in a cart and went on it.
"We did the Jurassic Park bit together and the Back to the Future ride which we were both incredibly excited about, we loved it. That was our bonding moment." * National Treasure 2: Book of Secrets is released on February 8.