When Brandi Carlile and the Foo Fighters' Dave Grohl decided to busk on the streets of Seattle, the internet was thrilled. But as it turns out, they're working on something more substantial than a one-time live collaboration.

Going back to Seattle's Pike Place Market was emotional for Carlile. The location where she and Grohl played is exactly where she used to busk for tips as an up-and-coming musician.

“It was really surreal because I used to stand right there with all my hopes and my dreams and the two chords that I knew, trying to make gas money," she recalls in an interview with Rolling Stone.

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Carlile and Grohl have more in common than meets the eye. They have the same guitar tech that Nirvana used, Ernie Bailey. They spent their day together in the city talking about some of their "scallywag shenanigans" and visiting places that influenced Carlile as an artist and person.

Carlile divulged that since the Foo Fighters are currently taking a break, Grohl has tapped her for a mysterious project.

“I don’t totally want to give it away, but he came out to my house to talk to me about something he’s working on," Carlile explained. "It’s more like one of his docuseries. We hung out and rode four-wheelers around my house all day, cooked dinner and did shots of tequila – just had a great time.”

Any fans of the Foo Fighters know that Grohl is always up to something musically and in his life, including the Backbeat BBQ business he's currently undertaking. Last year Grohl's mother Virginia confirmed that there is a film in the works about her son's life. The movie will focus on everything "from Scream to Nirvana to Foo Fighters."

Fans already began speculating on what this new project could be: perhaps a new installment of Grohl's Sonic Highways docuseries? Or a new series altogether? Something about Carlile as an artist or a collaborative piece? Nothing is certain besides the fact that both fanbases are excited about the new project.

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