It posits a Victorian-era Britain in which great technological and social change has occurred after entrepreneurial inventor Charles Babbage succeeded in his ambition to build mechanical computers.

Although Wellington stages a coup d'état in 1830 in an attempt to overturn his defeat and prevent the acceleration of technological change and social upheaval, he is assassinated in 1831.

The novel explores the social consequences of an information technology revolution in the nineteenth century, such as the emergence of "clackers" (a reference to hackers), technologically-proficient people, such as Théophile Gautier, who are skilled at programming the Engines through the use of punched cards.

Indeed, they are collectively called "savants" and often raised to the peerage on their merits, causing a break with the past as regards social prestige and class distinction.

Japan is awakening after the British ended its isolation, and looks, as in our timeline, set to become one of this world's leading industrial and economic powers from the 20th century onward.

Among other historical characters, the novel features "Texian" President Sam Houston, as an exile after a political coup in Texas, a reference to Percy Bysshe Shelley (as a Luddite), John Keats as a kinotropist (an operator of mechanical pixellated screens), and Benjamin Disraeli as a publicist and tabloid writer.

The action of the story follows Sybil Gerard, a political courtesan and daughter of an executed Luddite leader; Edward "Leviathan" Mallory, a paleontologist and explorer; and Laurence Oliphant, a historical figure who, as is portrayed in the book, was a travel writer whose work was a cover for espionage activities "undertaken in the service of Her Majesty".

However, he wants information that would compromise her seducer, Charles Egremont MP, now regarded as an obstacle to the strategies and political ambitions of Lords Brunel and Babbage.

Sybil has longed for an opportunity for vengeance against Egremont, and the resultant political scandal destroys his parliamentary career and aspirations for a merit lordship.