Once upon a time there was a great queen who, having given birth to twin daughters, invited twelve fairies who lived nearby to come and bestow gifts upon them, as was the custom in those days. Indeed, it was a very useful custom, for the power of the fairies generally compensated for the deficiencies of nature. Sometimes, however, they also spoiled what nature had done its best to make perfect, as we shall soon see. ("Green Serpent")