‘1923’ Season 2 Co-Stars Fall IN LOVE On Set!

Warning: This post contains spoilers for the 1923 series finale.

1923 was life-changing in more ways than one for Brandon Sklenar and Julia Schlaepfer.

The actors played beloved onscreen couple Spencer and Alex Dutton in the Yellowstone prequel series, which came to a heartbreaking end on April 6 as the lovebirds had a long-awaited and emotional reunion — only for Alex (Schlaepfer) to die after giving birth to their son, John.

Speaking to PEOPLE about the devastating finale, Sklenar, 34, reflects on the off-screen bond he developed with Schlaepfer, 30, in the years since they landed the “life-changing” roles.

“It’s a lot, you know? We spent almost three years with these people. And I’ve never done a series before and it was…such an incredible life experience for Jules and I,” Sklenar says.

Chemistry came easily for Brandon Sklenar and Julia Schlaepfer on the set of 1923 — so much so that their castmates thought they’d been friends before they were cast.

It was love at first sight for Sklenar and Schlaepfer’s beloved onscreen couple Spencer and Alexandra Dutton, who met in season 1 at a resort in Africa while Alex was technically engaged, only for her to ditch her husband-to-be (and family) to run away with Spencer.

Funnily enough, Schlaepfer tells PEOPLE their chemistry was just as instantaneous in real life.

“We showed up for day one of cowboy camp, and everyone in the cast thought that we knew each other. It was like our first conversation, and I remember one of my friends, Caleb, who plays Dennis in the show was like, ‘Oh my gosh, it’s so crazy. They cast two people who are super close already.’ And we were like, ‘We just met.'”

Schlaepfer, 30, continues, “We instantly just had a chemistry that was really special, and I think we both knew that we were about to embark on something really special, and so we both, I think, had this instinct to take care of one another and look out for one another.”

Their chemistry was instant, but the quality time they had together before season 1 even began filming helped too. The whole cast of the series was together for cowboy camp — Harrison Ford, Helen Mirren, Darren Mann and Michelle Randolph round out the rest of the Dutton clan, and Timothy Dalton, Aminah Nieves and Sebastian Roché also star — but it wasn’t long before Sklenar, 34, and Schlaepfer were on their own.

“Everyone started filming in Montana, the rest of the cast started filming in Montana, [and] we had a month until we left for Africa,” Schlaepfer recalls. “We’d just go ride horses together every day, we’d eat all our meals together, we got manicures and pedicures once together.”

“We just did all of the bonding, and then when we left for Africa, we were just by ourselves in Africa, so it was nearly impossible for us not to get thick as thieves,” she says. “Whether we wanted to or not, we were bonding.”

In this week’s issue, Sklenar reveals that he and Schlaepfer “didn’t chemistry read” before securing the roles, but rather, says creator Taylor Sheridan “knew that we would get on just by spending time with us individually.”

“And we had incredible chemistry from the jump, and it was so easy to work together and to fall into it,” Sklenar says. “I think a lot of that back and forth that’s on the page that Spencer and Alexandra have — that sort of banter and that shorthand — Julia and I just had that together as people. And that’s not something you can… If you don’t have that and you do those scenes, it’s not going to hit the same way.”

He continues, “You have to sort of have that vibe in how you communicate. And I’ll miss that for sure, having that type of scene partner and that type of work partner to play with in that space.”