“Enter Sandman” was written first for Metallica’s 1991 album Metallica, despite receiving its lyrics last.
The song’s central musical idea came from guitarist Kirk Hammett, who brought a riff to the songwriting process. James Hetfield and Lars Ulrich helped shape the arrangement, and the track became the first completed song idea associated with the album’s new direction.
Although the music existed early, Hetfield delayed writing the lyrics. The finished song uses the imagery of childhood sleep, nightmares, and the Sandman, giving a dark subject to an exceptionally catchy and direct rock arrangement.
“Enter Sandman” became the album’s lead single and one of Metallica’s signature songs. Its opening guitar figure, repeated vocal hook, and heavy groove helped introduce the band to listeners who had not previously followed thrash metal. The track’s success was central to the album’s breakthrough.