"He's what in England we call a bloke. He is a guy, and because he's a bloke, all the other blokes absolutely love him," Mirren said.

The actors, who play couple Jacob and Cara Dutton in the 'Yellowstone' prequel series, tell PEOPLE how they spend their time when the cameras aren't rolling

We had really good rapport, and I was lucky because almost 80% of my time is with him, and so he makes me laugh,” Geraghty tells PEOPLE