England. A century ago, give or take a few years. An England where people who are wicked in thought or deed are marked by the Smoke that pours forth from their bodies, a sign of their fallen state. The aristocracy do not smoke, proof of their virtue and right to rule, while the lower classes are drenched in sin and soot. An England utterly strange and utterly real. An elite boarding school where the sons of the wealthy are groomed to take power as their birthright. Teachers with mysterious ties to warring political factions at the highest levels of government. Three young people who learn everything they've been taught is a lie - knowledge that could cost them their lives. A grand estate where secrets lurk in attic rooms and hidden laboratories. A love triangle. A desperate chase. Revolutionaries and secret police. Religious fanatics and coldhearted scientists. Murder. A London filled with danger and wonder. A tortured relationship between a mother and a daughter, and a mother and a son. Unexpected villains and unexpected heroes. Cool reason versus passion. Rich versus poor. Right versus wrong, though which is which isn't clear.