Back to the Egg was billed as a "rock 'n' roll album." It featured a core lineup of Paul, Linda McCartney, Denny Laine, and Laurence Juber (guitar) with Steve Holley (drums). But it also boasted the "Rockestra"—a one-night-only basement tape jam featuring Pete Townshend, David Gilmour, John Bonham, John Paul Jones, and Hank Marvin. It was McCartney’s attempt to prove he could still rock with the heaviest hitters.