"It was great fun," Ford told ET's Cassie DiLaura on Friday at the Los Angeles premiere of 1923. "I mean, she's a wonderful, wonderful person and a fantastic actress. And it's just a pleasure to work with her again."
Mirren had similarly glowing things to say about Ford, recalling filming The Mosquito Coast "a great experience at that time."
"I was comparatively unknown, in America certainly, and not nearly as experienced as Harrison. So I learned a lot from him when we shot Mosquito Coast. It was fantastic to be reunited with him," the Oscar winner said, admitting that she "couldn't believe" it's been 36 years since they made the movie. "Actually, Harrison reminded me how long ago it was 'cause time does fly so fast!"
The latest to join Taylor Sheridan's Yellowstonefranchise, 1923 introduces a new generation of Duttons to viewers. The drama explores the early 20th century when pandemics, historic drought, the end of Prohibition and the Great Depression all plague the mountain west and the Duttons who call it home. Ford plays Jacob Dutton, John's great-great uncle, and Mirren portrays Cara Dutton, Jacob's wife.
"I think of it more as being part of an investigation of American history," Mirren said of being involved in the Yellowstone universe. "The trials and the struggles and the adventures of this one family over many generations. And I think that's sort of a brilliant way of looking at American history."
Co-star James Badge Dale, who plays John Dutton Sr., offered an intriguing glimpse into where viewers will find his character in 1923. (His character was introduced as a young boy played by Audie Rick in 1883.)
"I think this story is so beautiful. This family, they're kind of like pirates. It's a lawless time. People are trying to figure out who they are and what they represent and the story lives in that gray area," Dale said. "It's about men taking what other men have had and I think it's brave, risky material."
The official trailer for 1923 set up a violent existence for Jacob and Cara Dutton as they try to defend their land. When asked how far Jacob will go to keep his family safe, the Oscar-nominated actor had a simple response: "As far as it takes."
Unrelated to 1923, Ford briefly spoke about the response to the trailer for Indiana Jones and the Dial of Destiny, the latest installment in the movie franchise, which features a much younger Ford.
"This is a different kind of de-aging," he said. "This is actual archival footage of film of me at that age. So it's not digital, it's not. It's a different process. It's pretty remarkable. It blew me away."
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.