Unteholz is a city built on the backs of dying monsters. When Lena Sturm, the city executioner, learns that she executed an innocent priest, she sets out to find the real killer and bring them to justice. But her quest for the truth drags her into a web of conflict and conspiracy, with everyone from zealous Bishop to a mad alchemist as potential suspects. As Lena persues justice, an army marches on the city, intent on bringing it to its knees. With the pressure mounting and the city's future in danger, Lena must not only fight to uncover the truth but also to keep her adopted home safe.