Ten years have passed since the events of The Beast Player. Elin and Ialu are married, with a young son, living a quiet, peaceful life when one day Elin is called upon to investigate a matter of great urgency: the fearsome Toda are dying and nobody knows why. As Elin investigates, she uncovers a deadly plot and a brewing invasion. Can she protect her homeland without allowing her beloved beasts to be used as weapons of war, or will she have to compromise her principles to save her family?

Van, a former soldier made slave, toils away endlessly in a salt mine. An expected chance at liberation drops in his lap when a pack of infected dogs pass through, killing everyone but him and a young girl called Yuna. Van hopes to make a peaceful life for himself now that he’s escaped. However, the disease that cleared out the mine is rapidly spreading, placing him and his ward at the center of a conflict greater than any the world has ever seen.

Erin's family have an important responsibility: caring for the Toda, fearsome water serpents who form the core of their Lord's army. So when a number of Toda mysteriously die, it is Erin's mother who takes the blame, and the punishment - she is sentenced to death. Before she dies she manages to use an ancient forbidden power to send Erin to safety - leaving her daughter alone, far from home but with the knowledge that both she and her mother are somehow different.

Soon, Erin finds she can talk to both the terrifying Toda and the majestic Royal Beasts, who protect the supreme queen of her realm. This knowledge gives her great power, but it also involves her in deadly plots and political gameplaying that she wants no part of. Can Erin save herself and prevent her beloved beasts from being used as tools of war, or is there no way of avoiding the terrible battles to come?

Van resolves to fight the Zol Empire and save his homeland, only to be captured and sent to the salt mines. Then one night, a pack of wild dogs attacks the mine, trailing a mysterious and deadly disease in their wake. Van and a young girl named Yuna are the sole survivors of the disaster. But why? And where do they go from here?