It is 1863, but not the one it should be. Time has veered wildly off course, and now the first moves are being made that will lead to a devastating world war and the fall of the British Empire.

The prime minister, Lord Palmerston, believes that by using the three Eyes of Naga—black diamonds possessing unique properties—he’ll be able to manipulate events and avoid the war. He already has two of the stones, but the third is hidden somewhere in the Mountains of the Moon, the fabled source of the Nile.

Palmerston sends Sir Richard Francis Burton to recover it. For the king’s agent, it’s a chance to redeem himself after his previous failed attempt to find the source of the great river. That occasion had led to betrayal by his partner, John Hanning Speke. Now Speke is leading a rival expedition on behalf of the Germans, and it seems that the battle between the former friends may ignite the very war that Palmerston is trying to avoid!

Caught in a tangled web of cause, effect, and inevitability, little does Burton realize that the stakes are far higher than even he suspects.

A final confrontation comes in the mist-shrouded Mountains of the Moon, in war- torn Africa of 1914, and in Green Park, London, where, in the year 1840, Burton must face the man responsible for altering time: Spring Heeled Jack!

Burton and Swinburne’s third adventure is filled with eccentric steam-driven technology, grotesque characters, and bizarre events, completing the three-volume story arc begun in The Strange Affair of Spring Heeled Jack and The Curious Case of the Clockwork Man.

From a haunted mansion to Bedlam madhouse, South America to Australia, séances to a labyrinth, Burton struggles with opponents and inner demons, as he meets the philosopher Herbert Spencer, Florence Nightingale, and the father of Sir Arthur Conan Doyle.

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!

They stand at a crossroads in their lives and are caught in the epicenter of an empire torn by conflicting forces: Engineers transform the landscape with bigger, faster, noisier, and dirtier technological wonders; Eugenicists develop specialist animals to provide unpaid labor; Libertines oppose repressive laws and demand a society based on beauty and creativity; while the Rakes push the boundaries of human behavior to the limits with magic, drugs, and anarchy. The two men are sucked into the perilous depths of this moral and ethical vacuum when Lord Palmerston commissions Burton to investigate assaults on young women committed by a weird apparition known as Spring Heeled Jack, and to find out why werewolves are terrorizing London's East End.

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 all!