In a land ruled by fierce winged warriors known as eagle garudas, twelve-year-old Nargis is just a poor, lowly human, a Worm who hates the garudas that killed her parents. But even though she can't fly—and her childhood attempt left her walking with a crutch—she is far from powerless. Nargis is aspirit singer: able to coax small bits of wind, water, fire, and earth to do her bidding through song—well, sometimes.

When Nargis loses control of her power in a high-stakes kite fight, she is exiled. Cast into the desert, she discovers Mistral, an injured boy who turns out to be an eagle garuda, the prince of her enemies! He's on a mission to take back his throne from a terrible vulture garuda. In spite of their mutual distrust, the two have no choice but to forge an unlikely alliance if they want to escape the desert alive.

And as Nargis and Mistral battle dangerous assassins, befriend crafty sky pirates, and sneak into the mysterious sky castle of Alamut, Nargis discovers she carries a family secret, one that could bring Monsoon's rains back to the desert, but only if she's willing to risk her life in the bargain...