18. John Frusciante
In 1989, Eighteen-year-old John Frusciante, a bedroom-guitar prodigy from California's San Fernando Valley who had never played in a group before, auditioned for his favorite band, the Red Hot Chili Peppers. He got the job — replacing Hillel Slovak, who died of a drug overdose in 1988 — and transformed the Peppers' rascally punk funk into beefy arena pop. On the 1992 multiplatinum album, BloodSugarSexMagik, Frusciante fortified the band's bone-hard grooves with a mix of Hendrixian force and, in the hit ballad "Under the Bridge," poignant Beatlesque melody. When Frusciante abruptly quit the Peppers in the middle of a Japanese tour in 1992, he left a big hole in the group's sound that was only filled with his drug-free return on the Peppers' 1999 comeback album, Californication.