The American actress, 56, stars as successful author Sophie Brown, who travels to Scotland to escape a scandal, in Netflix romantic-comedy A Castle For Christmas.
And she admitted the lure of filming in Scotland for almost three months was among the key reasons for her taking on the role.
In the firm, Brown (Shields) hopes to buy a small castle, but the prickly owner Duke Myles, played by Cary Elwes, is reluctant to sell to a foreigner.
The pair clash, but soon find they have more in common than first thought.
The Golden Globe nominee, whose credits include Suddenly Susan and Lipstick Jungle, said streaming giant Netflix had made it clear to her it wanted to focus on empowered women over the age of 40.
She said: “I think we have come a long way. I really do. And I’m sure we still have more to go. We all do in every realm.
“But it was really refreshing to me to see that I was playing someone whose daughter was in college and who had a career and yet who still had such life in her.
“It’s refreshing. I do think it’s changing and I’ve been around for so long that I’ve seen all the machinations of it.
“I’m glad for the opportunity because I bring right now to this part something different than I would have in my 20s and I think that kind of celebration is great.
“And these two characters, they’re not looking to be saved. They’re not looking. They’re fine.
“And it’s not ever too late to open up your heart differently and trust your instincts. And that really to me comes with age and experience.”
Speaking about what attracted her to the film, Shields added: “What first drew me to the project is the way they explained it to me. Netflix said that they really are focusing on women over 40 and empowered women and that they wanted these stories to really exemplify what it’s like.
“Empty nester, full career and she doesn’t know what her next chapter is. And I think that that really initially triggered my interest.
“And then a rom-com and the fact that I was going to be able to work with Cary – all of these things. And in Scotland for almost three months.
“Every day was like ‘oh and there’s knitting and there’s whisky and there’s clubs and there’s dogs and horses. What?’ So it was heaven to me.
“And it was nice just to play my age and really be someone who wasn’t looking to be saved as a character and who finds more of herself in this environment.”
Elwes said the film would immerse audiences in Scottish culture at a time when many are still unable to travel freely due to the pandemic.
He said: “It’s like an escapism too because we get to celebrate and promote Scottish culture and Scottish history in this film. And so that’s also like a little bit of [escapism for] people who can’t travel during Covid.
“It’s like a little escapism. You get a little bit of a trip to Scotland.
"You get to see what it’s like and, believe me, we stored every aspect of Scottish culture that we possibly can and celebrated.”
A Castle For Christmas, which is directed by Mary Lambert, launches on Netflix today.