Adam Horovitz was in his early 20s and riding high on the Beastie Boys' 10-times platinum debut album when he bumped into Axl Rose at a star-studded Hollywood party in 1988. And the Guns N' Roses frontman had something to get off his chest.

"You know, we’re drinkin,' it’s this huge house up in the hills somewhere – and everybody’s there and I’m gettin’ drunk, and it’s like, next thing I know, I turn, I’m on the dance floor, and George Michael’s just standing next to me," the star-struck Horovitz, known as Ad-Rock in Beastie Boys, recently told GQ magazine. "I’m like, 'This is awesome.' And then Axl Rose came, like, stepped to me at the party and told me to stop ripping off Led Zeppelin. I’m like, 'How am I even ... how is this even happening?'"

"Rhymin & Stealin,'" from 1986's Licensed to Ill album featured a sample of John Bonham's drum track from Zeppelin's "When the Levee Breaks," and "She's Crafty" from the same album utilizes Jimmy Page's riff from "The Ocean."

Stories like his early interaction with Rose – who was possibly joking, since he was an admitted N.W.A fan – are sure to be expanded upon in an upcoming book that Horovitz is working on with fellow Beastie Boys co-founder Michael Diamond, aka Mike D. "We're still in early stages, even though we're supposed to turn it in in a couple of months," Horovitz said. "It's not gonna be out for a while."

Diamond, Horovitz and the late Adam Yauch (aka MCA) were inducted into the Rock and Roll Hall of Fame in 2012. Horovitz's next project is a starring role in While We're Young, a Noah Baumbach-directed film starring Ben Stiller and Naomi Watts.

Listen to the Beastie Boys' "She's Crafty" From Licensed To Ill

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