Shelby Lynne, Peter WolfShelby Lynne's duet with Peter Wolf on his song, 'Tragedy' -- the first track on the rocker's April 6 release 'Midnight Souvenirs,' marked the beginning of what both singers predict will be a lasting friendship.

Although Shelby was working on her own album, 'Tears, Lies & Alibis,' when the former lead singer of the J. Geils Band reached out to her, she couldn't resist joining him on the duet.

"Peter is a friend," Shelby tells The Boot. "The song is great, the band is killer. He's a great passionate musical dude, a great gentleman of rock ... I've wanted to work with him for a while."

The chance arose when Wolf and collaborator Angelo Petraglia of Kings of Leon discussed possible duet partners for the tune. "We were just tossing lines back and forth," Wolf says, "and thinking how perfect this song would be for me and one of our vocal favorites, Shelby Lynne. I've always been a fan of Shelby's, but I never met her."

After meeting, the two soon recorded the song in in Los Angeles. Calling Shelby's signature, smoky voice "real soul," Wolf says the recording sessions not only produced a great song but a personal kinship.

"It felt like we'd known each other forever," says Wolf. "That session began a very close friendship."

Peter's new album also includes duets with Merle Haggard on 'It's Too Late To Be Me,' and Neko Case on 'The Green Fields of Summer.' Shelby's new album is due April 20.

Download Shelby Lynne Music | Shelby Lynne on AOL Music

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