Dolly Parton

Track features Paul McCartney and Ringo Starr.

The ad features her cover of "We Are the Champions."

It's the fourth single she's released off her upcoming 'Rockstar' album.

See what she wrote him.

Track featuring the late Lynyrd Skynyrd singer appears on her upcoming album, 'Rockstar.'

It must have seemed like a good idea on paper.

Tracks are from country legend's guest-packed rock album 'Rockstar.'

Parton even wrote a song for Jagger, but he thought it wasn't a good fit.

"I hope it is something that will touch you and maybe touch enough people to want to make a change for the better," country star says.

Guests include two surviving Beatles, Steve Perry, Rob Halford, Ann Wilson and two late Lynyrd Skynyrd members, among many others.