Helen Mirren embraces change, ignores the rules

“You can’t overthink it,” she continues. “You just have to do it.”

It’s good advice from a 77-year-old screen icon, who just spent time driving a horse-drawn buggy through the rugged mountains of Montana. All in a day’s work for Mirren, who stars in the “Yellowstone” spinoff “1923,” which starts streaming Sunday on Paramount+.

The origin story Western focuses on the previous generation of the Dutton family as they struggle to survive historic drought, lawlessness, Prohibition and cattle theft during Montana’s great depression, which proceeded the rest of the nation by almost a decade. Mirren and Harrison Ford portray Cara and Jacob Dutton, the brother of “1883’s” James Dutton.

“Cara and Jacob have an incredible marriage where they’re really honest with each other,” the London-born Mirren says in a phone interview. “It’s not just love or lust, but a relationship seen through clear eyes, which makes it even stronger.”

Mirren has a strong grip on her own good life. She offers a little advice:

— Take a wild swing: Mirren isn’t exactly known for doing Westerns, but she jumped at the chance to star in “1923.” “I’ve always been fascinated by American history — especially the American West,” she explains. “Many years ago, I took a train from San Francisco to Detroit. I went through the Rockies, the desert and across the amazing Plains. All I could think of was the people who came west and walked or rode their way across this rugged land. You think about the effort, courage and struggle of it all. … American history is quite present in this series. We’re talking about my grandparent’s generation. It all felt within reach, and that was wonderful.”

— Cowgirl up: Mirren had a little experience with cowboys during that first trip west. Her train stopped at a few Western bars. “I had drinks with cowboys, who were such rugged characters with amazing stories, and then I got on the train again.” It made an impression, yet not as big of one as driving a horse-drawn buggy for “1923.” “It’s not easy because there are two of them and one of you,” she says of the horsepower.

— Don’t act your age: Mirren doesn’t hide her age. In fact, she has been called “sexy in her 70s,” which makes her smile. She’s good at putting it all in perspective. “To desperately try to pretend that aging isn’t happening is silly,” she says. “You can obviously try to make yourself feel and look as good as you want. That’s legitimate. But, at the same time, you have to find a way to deal with the fact that you’re getting older. I’m older! Everyone is always getting older. It’s better than the alternative. … I choose to celebrate the time. Celebrate the days with those you love. I’m proud to say that I’m doing everything I’m doing at my age and plan to do it for many more years.”

— Skip the bravado: Mirren is the first one to marvel at her celebrated career. “I’ve toddled on in my own sweet way doing my thing,” she says of roles that have included “The Queen,” “Red,” “Gosford Park,” “Hitchcock” and her TV series “Prime Suspect.” “Of course, I feel undeserving like everyone else does, too.” She says the joy of it is meeting fans who bring up a slew of different things. “One day, it will be, ‘Tell us about doing ‘The Queen,’ and the next, someone will bring up Mrs. Tingle.”

— Shake things up: Upcoming roles for Mirren range from the comic book flick “Shazam! Fury of the Gods,” where she plays Hespera, to “Golda,” where she will portray Golda Meir. “For me, the trick is to constantly shake it up a bit and never do the expected,” she says. “You need to surprise people in life. … Sometimes, you find yourself up a creek without a paddle, but that’s the risk you must take because even that journey to the creek can be an adventure.”

— Make your own rules: “Don’t allow others to make the rules for you. Make your own rules, meaning basically there are no rules! … As I get older, I realize that so many of us are stuck in the structure of rules. One of the great things about being an actress is that everything is constantly changing, which means you change your habits, your location and your mannerisms for a certain character.”

— Celebrate a strong union: Mirren has been married to acclaimed director Taylor Hackford (“Ray,” “An Officer and a Gentleman”) since 1997. What makes it work? “We do take an interest in each other’s work, and we’re there for any advice, but we also allow each other freedom.”