Hillel Slovak (Hebrew: הלל סלובק; April 13, 1962 – June 25, 1988) was an Israeli-American musician best known as the original guitarist and founding member of the Los Angeles rock band Red Hot Chili Peppers. Prior to his death of a heroin overdose in 1988, Slovak recorded two albums with the band, Freaky Styley (1985) and The Uplift Mofo Party Plan (1987). His guitar work was primarily rooted in funk and hard rock, although he often experimented with other genres including reggae and speed metal. He is considered to have been a major influence on the Red Hot Chili Peppers' early sound.
Born in Haifa, Israel, Slovak immigrated with his family to the United States when he was five years old. Slovak met future band mates Anthony Kiedis, Flea, and Jack Irons while attending school in Los Angeles. He joined the group Anthym along with Irons while attending Fairfax High School; Flea would later join the group, which later changed its name to What Is This?. Slovak, Flea, Kiedis, and Irons started Red Hot Chili Peppers in 1983, which became popular in the Los Angeles area, playing various shows around the city. However, Slovak quit the band to focus on What is This?, which had gotten a record deal, leaving the Red Hot Chili Peppers to record their debut album without him. He rejoined the Chili Peppers in 1985, and recorded the albums Freaky Styley and The Uplift Mofo Party Plan with the band.