Ralgwin is determined to avenge his uncle and carry out his mission of overthrowing the Forthorthian royal families, but it's becoming increasingly clear that the villains he's assembled to assist him don't necessarily share his goals. The rebel leader is in for a betrayal he never saw coming, with far more at stake than he ever imagined.

Meanwhile, Koutarou and the girls are preparing for the dramatic unveiling of the new Blue Knight, Forthorthe's first knight-class battleship. A preliminary inspection of the craft turns up an unexpected development—a shadowy new face asking them to do the unthinkable.