Fresh from their victory over the frightening chimerae monsters, Kie and N'Rah are looking forward to a quiet life on her uncle's orchard, far from the turmoil of the capital city. They miss the friends they made there, but as sky couriers, their job keeps them busy.

Then Kie unexpectedly receives a message from the emperor himself! He has an urgent mission for Kie and N'Rah--they need to find the Sky King, the elusive ruler of the wild skysteeds that soar across the land. After losing so many fighters in the Battle of a Thousand Chimerae, the empire is in desperate need of a hundreds of winged horses for their soldiers to ride. The wild herds are the only source, but bitter betrayals in the past have made the Sky King distrustful of humans.

Kie's unique gift of communicating with all skysteeds makes her the best person for the job, but it would take a miracle for the Sky King to trust a young girl. Then a new threat emerges in the form of huge birds of prey called vultiren. With the fearsome creatures heading straight for the wild skysteeds' hidden refuge, Kie must convince the Sky King to ally with her--before their world is destroyed forever.