Once dragons ruled the Rain Wilds, tended by privileged human servants known as Elderlings. But now the magnificent creatures have been driven nearly to extinction—and the last of their kind, born weak and deformed, have one last hope of survival: to return to their ancient city of Kelsingra. After a long and harsh journey, Kelsingra is finally near, on the far side of the toxic Rain Wild River. But the greatest trial still lies ahead for the dragons and their human keepers. Rapidly approaching enemies driven by wickedness, greed, and dark desires covet the treasures that await within the magical city's walls. And to reach their ancestral sanctuary, the dragons must reawaken a power lost to them generations earlier. The dragons must learn to fly.