Boomtown Los Angeles, 1929. The movies have burst into song and speech and aircraft into the skies at speed. Into this world of soundstages and speakeasies comes Xas, stunt flier and wingless angel, with his French pilot's licence and his broken heart, determined only to go on living in the air. What does it take to turn a wind? Will it be Conrad Cole, movie director and aircraft designer, a glory-seeking king of the grand splash who is also a man sinking into his own sovereign darkness? Or will it be Flora McLeod, film editor and maimed former actress, who sees something in Xas that no one has ever seen before, not even God, who made him, or Lucifer, the general he once followed - Lucifer, who has lost him once but won't let that be the end of it? What does it take to turn a wind? Mountains. Or another wind.