The 27th volume in Perry's long running and popular historical mystery series featuring Charlotte and Thomas Pitt. It's 1897, and the British Empire is beset from without and within. Thomas Pitt, Commander of Special Branch, is responsible for protecting the security of the state from its enemies. But there are those who wonder if he is up to the job.
A macabre scene has been discovered outside a house on Shooters Hill near Greenwich. The evidence suggests a vicious attack in the dark hours of a freezing cold night. There are bloodstains, shattered glass, and matted hanks of long auburn hair. And an auburn-haired lady's maid, Kitty Ryder, has disappeared from that same house that very night. Pitt and his trusted assistant Davey Stoker are called onto the case because the house belongs to Dudley Kynaston, who works on new weapons for the British Navy, with access to vital military secrets.
But although Kitty Ryder has disappeared, seemingly without a trace, from Kynaston's household, without more definitive evidence, Pitt's investigations are stymied. Then, a few weeks later, a corpse mutilated beyond recognition, but physically the same size and coloring as the missing Kitty, turns up in a gravel pit on Blackheath not far from Shooter's Hill. Is it Kitty Ryder? And where has the body been befoe it was left in the gravel pit? As Pitt continues to ask questions, he uncovers slight inconsistencies in Kynaston's story. Are these harmless omissions or simple coincidences, or could they be more sinister evidence that implicates Kynaston in treason?
Pitt knows he cannot afford to make an accusation that he cannot prove. In his job, his successes will all be secret but his failures will be appallingly public.