Enter Sandman was the first song written for Metallica's 1991 album Metallica.
The song began with a guitar riff by Kirk Hammett, which he developed after hearing a demo from producer Bob Rock. James Hetfield and Lars Ulrich then helped shape the arrangement, lyrics, and final structure. Although it was written first, it was the last of the album's songs to receive lyrics.
The track became the album's lead single and one of Metallica's signature songs. Its lyrics draw on childhood fears and bedtime imagery, giving the heavy music an instantly recognizable contrast between menace and familiarity.
The recording was not the first demo work associated with the album. Demos for Enter Sandman, The Unforgiven, Nothing Else Matters, and Wherever I May Roam were recorded on August 13, 1990, before the full sessions began.