According to drummer
Nicko McBrain, the track is a remake of one of the band's earlier songs, entitled "Floating", of which "Purgatory" is a faster re-arrangement. It was the group's least successful single as it failed to break into the Top 50 in the UK charts, although the group's manager,
Rod Smallwood, states that this was because "it wasn't really a single, it was just lifted off the album which the fans already had." Most notably, the single's original cover artwork was withdrawn for use on the band's next studio album,
The Number of the Beast. This meant that the band's artist,
Derek Riggs, had to come up with a replacement, this time illustrating the Devil's face rotting away to reveal the band's mascot,
Eddie's, face underneath. ==Track listing==