There aren’t four more recognizable or legendary faces in music—country or otherwise—than those that comprised supergroup The Highwaymen. Formed unintentionally in 1984 in Montreux, Switzerland, when Johnny Cash invited Kris Kristofferson, Willie Nelson, and Waylon Jennings to be guests on a Christmas special he was taping, the foursome found a collaborative creative fire that would etch itself forever into the lore of country music.

“There’s the four of us standing there, grouped around microphones,” wrote Jennings in his autobiography, Waylon: An Autobiography. “The Highwaymen. John, Kris, Willie, and me. I don’t think there are any other four people like us. If we added one more, or replaced another, it would never work.”

Having four established artists known for doing what they want, when they want, work together is the sort of endeavor that can explode brilliantly or implode dramatically with equal ferocity. When it came to playing live for The Highwaymen, it was almost the latter, until the moment when they found a way to come together. Jennings addressed this in his book as well.

“When we first took The Highwaymen out live, it looked like four shy rednecks trying to be nice to each other. It almost ruined it. That didn’t work, for us and the audience, and it was really bothering me, how different we were on stage than when we were sitting around in the dressing room. [At one point] I was fixin’ to quit. I talked to John about it and he was feeling the same way. ‘I get a little nervous,’ he said. ‘I don’t want to look like I’m trying to steal your thunder.’ That was it. We were boring each other and the audience. It may be hard to think of Johnny Cash as intimidated, but that’s the way we were. You can’t have four big guys tiptoeing around each other on stage. Nobody has a good time. By the end of the week, with Willie dancing across the stage and John and Kris singing harmony neck-and-neck, we had the wildest show, and it made us a group.”

Over the course of their decade-long run, The Highwaymen released three records, charted multiple singles, and won a Grammy for Best Country Song for their tune, “Highwayman,” as well as playing barn-burner live shows that will forever rate as “you should have been there.” You can watch part of one of those performances below, featuring the song “Desperados Waiting for a Train,” filmed March 4, 1990, at the Nassau Coliseum in Uniondale, New York.

While there will never be another group like The Highwaymen, their legacy lives on with a celebratory new multimedia box set, The Highwaymen Live—American Outlaws, out May 20. Featuring unreleased footage—including the entire Nassau concert as well as Farm Aid performances—and songs, as well as wildly fun to read liner notes from music scholar Mikal Gilmour, the box set is complemented by a PBS documentary, American Masters—The Highwaymen, ’til the End, which premieres May 27.