Kirk Hammett is best known as the lead guitarist of Metallica, having appeared on every release by the heavy metal band since 1983's Kill 'Em All. He was born in San Francisco, California, on November 18, 1962, and formed the thrash metal band Exodus in 1979. Only 16 years old at the time, Hammett helped steer the band during its infancy and played guitar on Exodus' three-song demo in 1982. One year later, he left the group to join Metallica instead. Hammett's guitar riffs quickly became a key part of Metallica's sound, and he co-wrote many of the band's signature songs, including "Enter Sandman" (1991), "The Unforgiven" (1991), "Hero of the Day" (1995), and "Fuel" (1998). While remaining an active member of Metallica during the 21st century, he also began exploring projects outside of the band. Blood In, Blood Out, the 2014 album by his former band, Exodus, featured a guitar solo from Hammett on the song "Salt the Wound." Nearly a decade later, he made his long-awaited solo debut with Portals, a four-song EP that he recorded over a three-year period. Produced by Bob Rock, Portals was released in April 2022, reaching Number 87 on the Billboard 200 and Number 12 on the US Top Rock Albums chart.