Only three stones of power remain, and only the eight descendants of Zubin can wield them. It is 20 years since Astreya learned the lore of the stones while discovering his origins and destiny, chronicled in The Astreya Trilogy. Now, a ruthless and power-hungry man is intent on stealing the stones, murdering the three leaders of the fleet, and torturing the secrets of navigation from their children.
Grand Master Astreya entrusts the last shipstone to his daughter Mairi, along with command of a ship, and instructions to keep the younger members of the family far from danger.
Mairi must face political turmoil ashore, resolve conflicts with her twin brother Trogen, and lead her young crew through storms, dangerous passages, and battles at sea before they can discover the full potential of the river of stones.