Roan follows Dara back to Turien to keep an Ancient device out of the hands of those who would use it for evil. There they find an army has risen up out of the earth and the sea to attack the city state, leaving death and destruction in its wake. When Mac, a teenaged girl with more sense for mechanics than keeping out of trouble, is captured by the leader of the invading army, Roan is once again presented with a choice between his human and his Ancient Blood.
Even on the brink of ruin, Turien holds no welcome for her would-be heroes. Caspian's father has put out a bounty on his son's head that ensures the city guard will be on the lookout. Tension mounts as each member of the company finds their loyalties shifting, their secrets exposed, their questions unanswered. Who is Auhle, why is he after the device, and what does an old hermit cast out of the Watchers' society have to do with it?