City on Fire is a fantasy novel by American writer Walter Jon Williams, first published in 1997 and nominated for the Nebula Award (for Best Novel) in 1997 and the Hugo Award (for Best Novel) in 1998. It is the sequel to 1995's Metropolitan. Plot summary The story begins shortly after the point where Metropolitan left off, with Aiah, the previous novel's protagonist, arriving in "Free Caraqui" to assist Constantine in his ambitions. In Caraqui, Constantine is confronted with intrigues among the other power players from the revolution, counter-coups, and war with the surrounding metropolises. He must also deal with the consequences of enlisting one of his more disturbing allies, Taikoen. Centuries previous, Taikoen was a powerful mage whose name passed into legend; he eventually transformed into a "hanged man," an entity of pure plasm whose only remaining drive is to possess other human beings and use their bodies to experience sensual pleasures until his victims die extremely gruesome deaths as a side effect of the possession. Constantine had made a pact with Taikoen to provide him bodies to feed on in exchange for destroying certain of his enemies, but is now wracked with guilt for doing this and is conflicted between his need to use Taikoen to further his ambitions and his worry that he has unleashed a monster he cannot control. Aiah eventually grows to become a minor power in her own right in Caraqui, serving as a government liaison to some Barkazi mercenary units Constantine has hired to defend Caraqui (among many others). Aiah befriends a military mage from one of those units who helps her eventually destroy Taikoen. Despite the conflict still raging, Constantine works to pursue his ultimate plan for the New City - nothing less than the destruction of the Shield that imprisons humanity in the world and the confrontation of whatever powers placed it there. Seeing plasm as the key to humanity's liberation, he enlists the help of Rohder, one of Aiah's old colleagues from the Plasm Authority in Jaspeer (and a minor character in Metropolitan). A centuries-old researcher-mage, Rohder had discovered new geometric properties that could boost the production of plasm in cities, with the unfortunate need to completely reorder their infrastructure at prohibitive cost. Fortunately, Caraqui is a metropolis built on pontoons in the shallows of one of the world's seas, so Constantine enables him to experiment by physically moving parts