New Londinium, the capital of the United Republic of Britannia, is the birthplace of the "clean steam" era and a haven for free-thinkers, progressives, and intellectuals. Its government relies solely on the advice of the Council of Danaeus, a collective of the world's pre-eminent scientists and inventors, to formulate the policies that make this city the most celebrated in the world. Yet something sinister is invading New Londinium - an immortality cult whose machinations to enslave all but a chosen few threaten to transform the city from a beacon of hope to a flagship of misery. So when the impoverished but undaunted Viola Winslow discovers her dead brother in a state of reanimation, she requests the assistance of renowned inventor, Doctor Parthena Ripley, and her feisty sister, Artemis Ripley Devereaux, to save him. However, it's not until Doctor Corazon Paget, the grande dame of the Council, disappears in suspicious circumstances and a series of explosions rock New Londinium that Parthena, Artemis and Viola truly understand the deadly game in play.