Run DMC's 1985 LP was almost completed when the Jam Master Jay spontaneously spun Aerosmith's classic "Walk This Way" in the studio. Run and DMC began rapping over the intro, giving producer Rick Rubin a great idea. "The album needed one more element," Rubin told Rolling Stone in 2009. "I thought there had to be a way to present this to rock fans so people would think, 'This really isn't that different than the kind of music I like.'" He asked Run and D.M.C. to rap Aerosmith's original lyrics. "We said, 'Motherfucker, this is hillbilly gibberish, this is fucking bullshit!'" D.M.C. told Rolling Stone in 2009. Russell Simmons insisted, and Rubin increased the pressure by inviting Steven Tyler and Joe Perry down to the studio. "We needed someone to play guitar and sing the chorus," Rubin said. "Who better than the people who do it every day?" The song was a huge smash, and it not only resurrected Aerosmith's career – it also introduced hip-hop to a white audience.