They’re getting along almost too well. That’s one instant reaction when viewing a new documentary on The Highwaymen, the first — and still, over 20 years later, the greatest — country music supergroup.

“The will to live big and dream big, and do what you want — that’s the message the guys would want people to get.”

There’s Johnny Cash, one of the best-selling recording artists of all time. Willie Nelson, a masterful songwriter and seminal example of turning your back on Nashville to chart your own path. Waylon Jennings, the living embodiment of outlaw country. And Kris Kristofferson, whose brilliant songwriting (and square-jawed good looks) made him a star in both movies and music, despite an atypical singing voice.

Watching “American Masters — The Highwaymen: Friends Till the End,” premiering tonight at 9 p.m. EDT on PBS stations, it’s hard not to think at first that some creative license must have been applied. A supergroup, by its very nature, just isn’t supposed to work this smoothly. There’s supposed to be jealousy and infighting — enormous egos crashing against each other, wrestling for creative control.

How could that not happen, considering the legendary status of the participants — referred to as “the Mount Rushmore of Country Music” — all unquestionable country superstars?

After a bit, any vestiges of cynicism melt away: You understand completely that these country megastars really were friends, and any demons they battled in their careers — and there were more than a few — were exorcised when the quartet performed together from 1985 to 1995.

Jim Brown, four-time Emmy winner and director/producer of the documentary, said that’s just how special the Highwaymen period was for the foursome.

“They were fiercely individual, four very individual characters, but they had this history of friendship,” Brown told LifeZette. “I think truly enjoyed each other’s company. Being on the road can be lonesome, and they were all road warriors. To go through that experience with each other, and with [a backing band composed of] all crackerjack musicians … it had to be fun.”

“They were all friends and fans of each other,” said Mickey Raphael, who played harmonica with the band on tour and on the three Highwaymen albums. “There really wasn’t any competition, [just] a lot of camaraderie.”

The Highwaymen produced some great music, and their live performances sold well, but fans might not remember that the band’s formation followed a relatively fallow period, for the most part, in their individual careers.

Who do you think would win the Presidency?

By completing the poll, you agree to receive emails from LifeZette, occasional offers from our partners and that you've read and agree to our privacy policy and legal statement.

[lz_third_party includes=”https://embed.spotify.com/?uri=spotify%3Auser%3Apopzette%3Aplaylist%3A4CBl93xRqKEzuz3fmETmis” align=”right”]

Jennings and Kristofferson were pushing 50, and Cash and Nelson had recently passed the half-century mark. On country radio, music by veteran artists wasn’t getting the play it used to, and record sales dropped off accordingly.

By getting together to form the Highwaymen — which was originally conceived as a one-off album, “Highwayman,” simply credited under their four names — Cash, Jennings, Kristofferson, and Nelson “really hit the jackpot,” Brown said.

The documentary coincides with last week’s release of a box set, “The Highwaymen Live: American Outlaws,” which includes three CDs and one DVD. Raphael, who produced the box set, said the music has been cleaned up and remixed to “really make it sound like it’s supposed to sound.”

“It’s a really big sound — everything’s so crisp and clear,” Raphael said. “And we included some of the mistakes, like: Kris is a poet laureate, but he’s not the best singer on the planet. On one track, even Kris’ guitar is out of tune. We just left it in there — it’s just who Kris is.”

Raphael, who has worked with Nelson for decades, said his tenure working with the Highwaymen was one of the high points of his career.

[lz_third_party includes=”https://www.youtube.com/watch?v=aFkcAH-m9W0″]

“It was so exciting to be around those guys and just to be a part of that band,” Raphael said. “They were just normal guys. Being around Johnny Cash, he was bigger than life, but he would go out of his way to make you feel comfortable. He was so accessible, him and June [Carter Cash],” Cash’s wife.

In addition to a handful of lovely live performances, “Friends Till the End” has a mix of old and new interviews, along with fun behind-the-scenes footage of the four icons. Jennings died in 2002, Cash in 2003, but their legacies live on through their individual recordings and those of the Highwaymen.

Brown was asked what he hopes will resonate with viewers of the documentary.

“The value of really believing in oneself and not being told that you’re finished is a message to a lot of middle-aged people that I would like to get out there,” Brown said. “The will to live big and dream big, and do what you want — that’s the message the guys would want people to get.”