Most people would be more familiar with the later rendition of the song by Naked Eyes released in 1982, so for Brooker to choose the version by the artist who first sang the demo is a choice that unsettles us. It sounds familiar, but you can't quite place it due to the different arrangement. There is something unsettling about thinking you know something but not quite being able to put your finger on it. Hearing the early version of the hit no doubt triggers the brain to think that it has heard the song before. It is familiar but different which encompasses the entire underlying principle of the show itself. The song mirrors our interaction with the show. The universe of Black Mirror is uncannily like our own, but just different enough to unsettle us.