When gods and demons clash, mortals bleed. A new mission brings Leda Pierce to her hometown on the edge of the Frontier. But in the six months since she left home to join the Legion of Angels in New York, things had gotten much worse. Crime lords now rule the city, and a vast number of beasts rage just beyond the great magical wall separating humanity from the plains of monsters. Along with the irresistibly seductive angel Nero, Leda leads a group of pilgrims through the monster-infested wasteland to the ruins of the final battle between gods and demons. However, what begins as a pilgrimage soon turns into a hunt for treasure—an ancient weapon that could tip the balance of power between heaven and hell—and spirals into intrigue that pits Leda and Nero against a rebel member of the Legion, a legendary angel equally powerful. how embittered. “Siren's Song” is the third book in the “Legion of Angels” series.