Harrison Ford and Helen Mirren on How Their Own Marriages Gave Authenticity to '1923' Relationship (Exclusive)

The stars of the 'Yellowstone' prequel talk to ET about how their real-life marriages helped their portrayal of Jacob and Cara Dutton.

Harrison Ford and Helen Mirren play husband and wife in Paramount+'s anticipated Yellowstone prequel, 1923, and the legendary actors credited their onscreen portrayal of a long-standing marriage to their own real-life partnerships with their significant others.

In the latest series to join the Yellowstone universe, which launches Sunday, Ford and Mirren portray Jacob and Cara Dutton, John Dutton's great-great uncle and great-great aunt, respectively. Mirren has been married to director Taylor Hackford since 1997, while Ford has been married to actress Calista Flockhart since 2010.

"It's a partnership, isn't it?" Mirren told ET's Cassie DiLaura during the 1923 junket at the Wynn Las Vegas on Dec. 4, of Jacob and Cara's marriage. "I may be the boss, but he's the leader. It's an equal partnership and I know from being with my husband [Taylor Hackford]. We've been married now for, I've completely forgotten how long we've been married for. But, you know, quite a long time."

"It becomes a partnership, a partnership with love, but a partnership and that's very much where marriage can be a long process and it has many phases that it goes through," the Oscar winner said. "But if you manage to stay together through love, you come to this very beautiful place where it is this equal partnership and I think that's where Cara and Jacob are."

Ford echoed Mirren's sentiments, saying that his marriage to Flockhart has informed the nuances of Jacob and Cara's union in the show.

"I suppose it helps, but I found working with Helen to be extraordinarily easy, simple, straightforward," the actor explained. "There’s no fussiness about her. She's a practical person. She's a down-to-earth person. She's very smart, very astute and she knows her craft. Our scenes have been nothing but a pleasure."

Paramount+

Both noted that their past history working together on the 1986 film, The Mosquito Coast, where they also played husband and wife, made the transition to 1923 quite seamless when they stepped onto the Montana set.

"I was quite well known in England, but not known in America at all. He was there and I was down there, not that he ever treated me that way incidentally. He was always very gracious, but it was very an unequal sort of thing and we loved working together. And then we went off to our own ways. I met my husband and we did everything that happened to us. We weren't in each other's lives, we occasionally met each other at parties and it was always very nice to see each other. But the minute I got back with Harrison, it was as if those years had just come together. But in a better way even because now I was more on an equal partnership," Mirren recalled.

"I will never be on the same level as Harrison ever but at least I'd climbed up a little bit," she added with a laugh. "And it was just this immediate connection. It was very extraordinary. And I feel it shows on the screen. There is this sort of natural ease we have with each other, which we do now."

Ford agreed, saying he felt the ease of playing Mirren's onscreen husband decades later. The Oscar-nominated actor shared that while Jacob is the patriarch of the Yellowstone ranch, it's really Cara who's the real boss.

"He knows it and he shows it, and that's just a part of the fabric of their lives. He does his thing, she does her thing. And they live comfortably together," he said.

Paramount+

Ford also credited Cara for supplying "a great deal of Jacob's strength," acknowledging that Jacob wouldn't be where he was without the support and strength of his wife by his side.

"That's certainly the case," Ford said, agreeing with the statement that behind every man is a strong woman. "I don't consider myself a great man, but I do have a great wife as well."

1923 premieres Sunday, Dec. 18 on Paramount+ in the U.S. and Canada. Paramount Network will have a special airing of the 1923 premiere on the same day following Yellowstone. The second episode will air Jan. 1 on the network.

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