The song is immediately recognizable by its central theme, a crunching four-tone chromatic progression that is perhaps the single most famous riff in heavy metal music history. This riff, played on electric guitar by Ritchie Blackmore, is immediately joined by drums and contrapuntal electric bass and organ parts before the start of Ian Gillan's expressive vocal. Despite the heaviness of the guitar part, constant movement and interplay within the supporting parts keeps the feel of the song from becoming leaden.
The lyric of the song tells a true story: in late 1971, Deep Purple had set up camp in Montreux, Switzerland to record an album using a mobile recording studio (rented from the Rolling Stones) at the entertainment complex that was part of the Montreux Casino (referred to as "the gambling house" in the song lyric). On the eve of the recording session a concert featuring Frank Zappa and the Mothers of Invention was held in the casino's theater; during the concert a fire broke out (said to be caused by a fan shooting a flare gun) that eventually destroyed the entire casino complex. The "smoke on the water" that became the title of the song referred to the smoke from the fire spreading over Lake Geneva from the burning casino as the members of Deep Purple watched the fire from their hotel across the lake. Left with an expensive mobile recording unit and no place to record, the band rented out the nearly empty Montreux Grand Hotel and converted its hallways and stairwells into a makeshift recording studio, where they laid down most of the tracks for what would become their most successful album, Machine Head.
Ironically, the only song from Machine Head not recorded in Montreux was "Smoke on the Water" itself; the basic tracks for the song were laid down in an empty auditorium elsewhere in Switzerland, in an effort to capture a reverberative sound.
"Smoke on the Water" was included on Machine Head, which was released in early 1972, but was not released as a single until nearly a year later (the band has said that they did not expect the song to be a hit); the single would reach #4 on the Billboard pop single chart in the U.S. in the summer of 1973, and propel the album to the top 10. Live performance of the tune, featuring extended interplay between Blackmore's guitar and Jon Lord's Hammond organ would become a centerpiece of Deep Purple's live shows, and a version of the song from the live album Made in Japan became a minor hit on its own later in 1973.