Lindsey Buckingham has revealed that the members of Fleetwood Mac had doubts over their contributions to the new duets album he wrote with Christine McVie.

His comments were made in a 17-minute documentary clip that goes behind the scenes at recording sessions for the LP, which arrives on June 9. The tracks “In My World” and “Feel About You” were released last month.

The project had its roots in McVie’s return to Fleetwood Mac in 2014, a move that led to a rekindling of a writing partnership with Buckingham. When Stevie Nicks decided she didn’t feel right about a new Fleetwood Mac record, Buckingham and McVie decided to continue working among themselves, before bringing in Mac bandmates Mick Fleetwood and John McVie to the project.

“One of the things we thought about was to create an environment that was a departure, but also one that was familiar and felt like home," Buckingham says in the above video. "We immediately thought of John and Mick, the greatest rhythm section there is. It was a wonderful idea on paper. Whether or not that played out remained to be seen. We didn’t go in assuming it was going to be wonderful. We knew we loved each other and we wanted to do it. But whether the process would be as enlightening and effortless as it seems to have been was another question.”

That comment is followed by a scene in Los Angeles' Village Studios, where Buckingham reports that they’ve been working together for only an hour but “the chemistry is running rampant here.”

McVie described the project as a “fresh beginning,” adding, “Coming back into the band after 16 years, and to take off into another level with Lindsey, again – I guess I’ve rediscovered by love for writing, my love for music.”

Buckingham and McVie will start a brief U.S. tour next month, while Fleetwood Mac appear at the new Classic East and Classic West festivals, in New York and Los Angeles, respectively, in July.

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