New documentaries about Loretta Lynn and the Highwaymen are coming to PBS in 2016, as part of the celebration of the 30th anniversary of the American Masters documentary series.

The Highwaymen -- a country music "supergroup" made up of Johnny Cash, Waylon Jennings, Willie Nelson and Kris Kristofferson that got its start in the mid-1980s -- will be the subject of The Highwaymen: Friends Till the End. The quartet released three albums over a 10-year period, and the TV special will showcase the four icons and the music they made together and will tell the group's story through footage of old performances and studio time, new interviews and more.

Lynn, meanwhile, will be profiled in another documentary, Loretta Lynn: Still a Mountain Girl. The show will explore Lynn's road to stardom as she went from a rural Kentucky farm girl to a world-class superstar; it will also show the singer trying to maintain balance in her home life and career.

“I think I’ve done quite a bit,” Lynn reflects. “I’m probably one of the girl singers who have helped other girl singers get in the business, because it is harder for girls to get on labels and be out there.”

The Highwaymen: Friends Till the End is set to premiere on May 27, while Loretta Lynn: Still a Mountain Girl will debut on March 4 -- the same day that her new record, Full Circle, is set for release.

Other country artists previously featured on American Masters include Merle Haggard  and Jeff Bridges.

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