The Darkening has risen...

Agathea Flamma and Sebastian Smith now face an overwhelming enemy. The rapid spread of the Darkening, a threat arising from the mists of legend, looms over the entire land. With both their families torn apart by the conflict and betrayal lurking around every corner, one mistake could doom the kingdom.

They'll have to decide where to put their faith: blood ties or newfound friends?

After the destruction of the Dragon Academy, it's up to Thea and Seb to gather their loyal comrades-and forge uneasy new alliances-to quell the ancient menace and face the evil Lord Vincent. With civil war raging, the Dragon Riders must race against time to find the legendary Dragon Stone, the only tool they have to fight against the endless darkness that threatens to swallow them all.