After traveling to the seaside kingdom of Lilah's betrothed prince, Lulath, Celie and her companions are busy training griffins, enjoying wedding festivities and finishing construction of a grand ship. But on their maiden voyage, the ship steers them far off course into uncharted waters. Celie and Lilah hope that the ship is taking them to the ancient island where unicorns once roamed, but as the journey grows longer and supplies run low, they realise they are in trouble....