Nightmare Fuel / Yes

This Progressive Rock band is generally thought of as being pretty light in tone, but they have their moments.
  • The music video for "Owner of a Lonely Heart" has some...disturbing scenes.
  • If the violent lyrical imagery in the beginning of "The Gates of Delirium" don't haunt you, or its dissonant midsection, the painting of the snakes crawling on the rocks on the back cover of its parent album Relayer just may.
  • "Machine Messiah" rocks just as hard as many of their metal contemporaries did, and contains nightmarish imagery and instrumental passages to match.
  • When "The Fish (Schindleria Praematurus)" was performed live, Squire would often turn the distortion of his bass Up to Eleven and unleash a storm of dissonance. For The '70s, this would have qualified as a hard 11 on the Mohs Scale of Rock and Metal Hardness, and probably still qualifies in the 6-7 range. An excellent example can be found on the band's seminal live album Yessongs.
  • The second half of Tales from Topographic Oceans can get pretty experimental and dissonant. Most of "The Ancient (Giants Under the Sun)" (the last five minutes are instead pretty close to being Sweet Dreams Fuel) and the instrumental midsection of "Ritual (Nous sommes du soleil)" can both be very unsettling.

http://tvtropes.org/pmwiki/pmwiki.php/NightmareFuel/Yes