Master of Puppets

Master of Puppets is a masterclass in 'Metal Harmony.' It blends strict functional harmony (especially in the clean interlude and chorus) with highly dissonant, chromatic riffing in the verses. The song uses the E low-string as a constant tonal center (pedal point), while the upper voices move through Phrygian and Locrian intervals. The transition from the aggressive, chromatic verse to the melodic, Aeolian chorus provides the structural tension and release that defines the genre.

The song was written by the entire band—James Hetfield, Lars Ulrich, Cliff Burton, and Kirk Hammett—making it the only track on the album to credit all four members. It was developed during rehearsals in the band's garage in El Cerrito, California, before they flew to Denmark to record.

Widely regarded as the pinnacle of thrash metal, this track showcases Metallica's technical precision and progressive songwriting. It balances aggressive down-picked riffs with a melodic mid-section, solidifying its place as one of the most influential songs in heavy metal history.