Helen Mirren and Harrison Ford go way back.

They played a married couple in The Mosquito Coast, a 1986 Peter Weir-directed drama, and developed deep mutual respect. But it would take 37 years for the beloved actors to reunite on screen. Now, costarring as a ranching couple in Yellowstone spinoff 1923, the pair are having a ball together.

“Helen is incredible,” Ford, 80, tells PEOPLE in this week’s cover story. “What a treat it is to work with her again.”

The feeling is mutual.

Mirren, 77, shares with PEOPLE how Ford, who also stars in Indiana Jones and the Dial of Destiny, out June 30, has changed — and stayed the same — in the last four decades:

“In his essence, Harrison Ford is the same person he was when I first met him. Impatient with the annoying sides of the great fame that had settled upon him, adult sycophancy, loss of privacy, etc., and yet immeasurably patient and kind to starstruck kids so excited to see their hero. His privacy was a profoundly protected place. His work was always beautifully designed and constructed, like the carpentry he was so well known for, and I was deeply impressed with his understanding and use of the techniques of film acting. He taught me a lot through my observations. He was professional, guarded, and mysterious, and I was both fascinated and intimidated.”

“Then 30 years of amazing life happened to both of us, and now we are reconnected, and I find a person not guarded, unafraid of feelings and expressing them; generous, funny, as professional as ever, and still impatient with stardom.”

“I think the element that makes him the legend that he is and will be is that sense of being the kind of guy you would call when your car got stuck in a ditch and also completely understand why you were so upset about your cat dying and shed some tears with you. He is a real god-given movie star, but also a chap, a geezer, a guy, a bloke and a mensch. And along with millions of others, I love him.”