Karen, a young underground soul caster, is forced to accept a dangerous commission from black market intelligence dealer Ilana in order to save her sister Lila who suffers from "soul decay" - to steal a "corrupted core" of the Inquisition. During the operation, they were chased by the chief inquisitor Valerius and narrowly escaped, but they were wanted throughout the city.
* When Karen was repairing the core, she accidentally discovered that there was a shocking secret hidden in it that the ruling class "Holy Light Council" artificially caused "soul decay" and harvested the souls of civilians. After learning the truth that her parents were murdered as a result, Karen's personal rescue goal was sublimated into a social mission of revenge against the entire system. With the help of his old acquaintance "Iron Hammer", he mastered the forbidden technology "Soul Resonance" that can broadcast memories.
Karen and Ilana's emotions sublimate in the test of life and death. They formulated the ultimate plan: to sneak into the "Prism of Holy Light", the core of the rule in the upper city, and make the evidence of the crime public. At the top of the Prism, they faced off against Valerius for the final showdown. After the collision of ideas and power, Karen successfully activated "soul resonance" at the expense of her own consciousness.
The truth spread throughout the city through the "Net of Resonance", triggering a revolutionary wave that overthrew the old order. Valerius' faith collapsed and he was defeated. Karen fell into a coma due to overdraft of his soul, and his life or death was uncertain, but an unknown transformation seemed to be taking place deep in his core. Ilana disappeared into the chaos before dawn with the Karen brothers and sisters, leaving suspense for the future and sequel of Iselgard.
