Quest for Ancient Colour by Manic Street Preachers
My interpretation of the song lyrics are that the protagonist is delving nostalgically into his/her youthful past - a place where everything seemed simpler & made more sense; as opposed to the present 'bad dream' (nightmare), which is reflective of the confusion & displacement they feel as they move through middle age in the modern digitized world. I would be very interested to hear other opinions & interpretations.