In a Victorian-era London beset by anarchists, detective Thomas Pitt investigates the mysterious death of Magnus Landsborough, the son of aristocrat Lord Sheridan Landsborough, during a violent gun battle between police and rioters.

In 1924, while visiting an old school friend's home for the annual Guy Fawkes celebration, Daisy Dalrymple Fletcher is stunned by the supposed suicide of the tyrannical head of the family, who may also have killed a guest.

In the spring of 1926, the corpses of three men are found in shallow graves off the beaten path in Epping Forest ouside of London. Called in to lead the investigation, DCI Alec Fletcher of Scotland Yard is under urgent orders from his supervisor at the Yark to accomplish two things: solve the mystery quickly, and keep his wife, the Honourable Daisy Dalrymple Fletcher far away from the case.

Thomas Pitt, once a lowly policeman, is now the powerful head of Britain's Special Branch, and some people fear that he may have been promoted beyond his abilities. He, too, feels painful moments of self-doubt, especially as rumors reach him of a plot to blow up connections on the Dover-London rail line--on which Austrian duke Alois Habsburg is soon to travel to visit his royal English kin. Why would anyone destroy an entire train to kill one obscure...

Investigating evidence of a violent struggle at the home of Ministry of Defense member Dudley Kynaston, Pitt and the Special Branch discover the brutally murdered body of a young woman before realizing that Kynaston is not who he appears to be.