In this musical comedy-adventure starring self-proclaimed greatest band in the world Tenacious D, a pair of aspiring rock superstars attempt to convince the world of their true talents as they embark on a daring quest to acquire the supernaturally powered guitar pick that will finally allow them to fully realize their vast rock & roll potential. JB (Jack Black) is a naïve Midwesterner whose strict Christian parents view his burning passion for heavy metal as a mortal sin. After his dad tears down every poster in his bedroom except for a Ronnie James Dio poster on the back of the door, the former Black Sabbath frontman instructs the aspiring young rocker to seek out his fortune no matter what the cost. Subsequently setting his sights on Hollywood and hellbent to take the world of rock music by storm, JB sneaks out his bedroom window and makes his way to Venice Beach, where he soon meets guitar-strumming slacker KG (Kyle Gass). With a future of rock & roll superstardom now well within their reach, JB and KG harness the power of Satan to form hellfire hard rock duo Tenacious D and set out on a quest to achieve musical immortality by stealing the mythical guitar pick said to instill its owner with unprecedented musical prowess.