Key is a blow-by-blow musical accompaniment to a childhood recollection. Almost every description in the text has been given a corresponding musical response, from ‘confidence verging on a swagger’ to ‘peaks of the range rising fantastically in the distance’ to name but two. The music is made of a set of 12 unique tonalities that are used melodically and harmonically.

The very first thing I can ever remember seeing with my own eyes was a young man walking across a bridge. He had a curly moustache and an attitude of confidence verging on swagger. He carried in his hand a disproportionately large key of a shining yellow metal and wore a large golden or gilded crown. The bridge he was crossing sprang on the one side from the edge of a highly perilous mountain chasm, the peaks of the range rising fantastically in the distance; and at the other end it joined the upper part of the tower of an almost excessively castellated castle. In the castle tower there was one window, out of which a young lady was looking. I cannot remember in the least what she looked like; but I will do battle with anyone who denies her superlative good looks.