In London, 1899, history is not quite as it seems. Queen Victoria still reigns, strange new technologies are reshaping the world, and bizarre crimes are leaving Scotland Yard's finest detectives baffled. When the mysteries become too strange to solve, Superintendent William Melville of the Special Branch has little choice but to call upon Music Hall illusionists Michael Magister and Phoebe Le Breton.

Between their sold-out performances, the sharp-tongued magician and his brilliant assistant find themselves drawn into a conspiracy of murder, occultism and sinister science. A satanic portrait painter threatens the Royal family, a deadly gas places the Government in peril, and a secretive group of psychopaths is led by the mysterious renegade Jesuit known only as The Black Bishop.

As Michael and Phoebe follow a trail of deception, treachery and strange inventions, they must decide who can be trusted in a world built on illusion. With the Tarot predicting death and enemies closing in, the greatest mystery may be the secrets surrounding the detectives themselves.