It is 1895, and the world is spinning into new discoveries each day, gaining momentum to unforeseen ends. Above this word that we know, there is another more ancient civilisation built on clouds, floating mountains, and magic. These people, including sirens, fauns and fae, are able to hear the Song, which allows them to make magic. The Song is a never ending mysterious melody, far beyond the hearing of a human, and with lyrics in a language from before the earth's beginning. From this great epic, a line is translated that predicts a catastrophic collision of worlds; in fifty years time, the humans will discover the realm in the clouds, and nothing will be the same again. Quin, a human secretly raised in the Sky Nation with a passion for cartography and flying his hot air balloon, hears of this prophecy and finds himself inexplicably intertwined with what is said to be fate. He travels with Pica, a young siren who is looking for the cause behind her sister's disappearance, and Oriax, a shadow siren looking for a place to call home, on a journey to find a mythical singing bowl that will help them stop a war- if it's in the right hands.