When Burton and Swinburne discover an abandoned brass man in Trafalgar Square, they find themselves on the trail of stolen black diamonds and embroiled in a plot involving the Tichborne Claimant and mysterious steam wraiths.

London, 1861. Sir Richard Francis Burton - explorer, linguist, scholar, and swordsman; his reputation tarnished; his career in tatters; his former partner missing and probably dead. Algernon Charles Swinburne - unsuccessful poet and follower of de Sade, for whom pain is pleasure, and brandy is ruin! Their investigations lead them to one of the defining events of the age, and the terrifying possibility that the world they inhabit shouldn't exist at...

Ex-cop Cliff Janeway is hired by an elderly woman to search for and recover a collection of rare works by nineteenth-century explorer Richard Burton which were stolen from her grandfather, Charlie Warren; however, others are also interested in the century-old treasure and will do anything to stop Janeway from succeeding.