Paul McCartney’s biggest surprise while headlining Lollapalooza last night (July 31) was inviting Alabama Shakes frontwoman Brittany Howard to the stage for a powerhouse duet (and guitar duel) on the Beatles’ classic “Get Back” that you have to see for yourself. Check out the action in the video player above.

Sir Paul’s headlining set at Lollapalooza 2015 last night (July 31) was a hit-fest from start to finish last night, and Alabama Shakes had already reached so deep into their souls that Howard had rocked the glasses clean off her face during one guitar solo. But the combination of both talents after dark and near the end of McCartney’s two-hour-and-fifteen-minute set was a special sauce of inspired collaboration.

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