This is a steam city with giant lungs as its heart and gears as its flesh and bones - Wulin City. Here, the Black Iron Council controls energy and order, while the gangs draw underground boundaries in the shadow of rain and smoke.
The protagonist **Cao Ran**, on the surface, is a down-and-out detective who was expelled from the Wulin City Detective Guild. In fact, he has the power of "original vision" and can see through any complex machinery and the context and "truth" behind the case. He was involved in a strange commission: tracking a steam armor that could "walk on its own", but during the investigation he discovered that he had already become a hunted pawn.
Just when he was under tight siege, Cui Yelan, an underground female overlord who called herself the "King Power Society", imprisoned him and asked him to decipher a black iron blueprint that no one could solve. However, Cao Ran discovered that this drawing was closely related to his amnesia past and a "destruction engine" that could subvert the entire city's power structure.
As the investigation deepened, Cao Ran discovered that his memory was not blank, but was forcibly blocked by a mysterious organization called the "Axiom Church." And the relationship between him and Cui Yelan has changed from a prisoner and interrogator to the only "accomplices" who can confirm each other's logic in the whirlpool of conspiracy - falling in love and killing each other, scabbarding each other.
When Cao Ran made a choice between "reason" and "truth"... The bells throughout Wulin City began to be chaotic for him.
