In 1870s London, Scotland Yard's famous Detective Department is still in its infancy. Surrounded on all sides by critics and detractors, it has yet to earn its reputation. Lord Riley Rochester, younger son of a marquess, works as one of its first detective inspectors---but his uniformed colleagues view him with suspicion and his immediate superior resents all he stands for. With his career choice frowned upon by his own social class, Riley has his work cut out proving himself. Attacked on all sides, Riley's only respite comes in the form of attractive widow, Amelia Cosgrove, and his effervescent niece, Sophia.
When a debutante is murdered in the home of Lord Ashton, a man who considers his position and reputation as a fragile framework for his ambitions, Riley's vengeful superior hands him the investigation, hoping to see him fail. As Riley and his sergeant, Jack Salter, delve into the circumstances surrounding Emily Ferguson's death, it quickly becomes apparent that his own class expect him to exonerate its members from all blame. But the murder was committed at a society event, and Riley's conscience won't allow him to ignore the evidence that points to one of the guests---or hosts---being the killer.
With Salter proving himself increasingly indispensable and Amelia unofficially helping with some of the more sensitive issues, Riley quickly discovers that the case is anything but straightforward. Everyone appears to have something to hide and no one seems to be telling him the whole truth. Fending off a mother determined to see Riley married and abandoning his career, and with Sophia clamouring for his attention, Riley is run ragged. Tempers fray as a heatwave holds London in its sweltering grasp and when a second death occurs, Riley fears he may be incapable of preventing a terrible miscarriage of justice.
As the tension escalates, Riley comes under increasing pressure to solve both murders. Will he and Jack manage to uncover the true identity of the killer without endangering those whom Riley holds most dear...
London 1870 Detective Inspector Rochester---Lord Riley Rochester---of Scotland Yard's Detective Department and his sergeant, Jack Salter, are called to a high-end brothel to investigate the murder of one of its inhabitants. Her throat has been cut from ear to ear after the customers had left for the night and the doors had been locked, and no one admits to hearing a thing.
As Riley and Jack delve into the beautiful young victim's background and the reasons for her fall into prostitution, an increasing number of suspects with compelling reasons for wanting her dead emerge. Riley is astounded to discover that his nemesis, Chief Inspector Danforth, is one of the brothel's regular visitors. He was there on the night of the murder, spent an hour alone with the victim and must be viewed as a suspect. Riley could be forgiven for revelling in Danforth's downfall after all the insults he has suffered at the chief inspector's hands, but his concern is for the reputation of the Detective Department as a whole and so he does all he can to shield Danforth from public derision.
Unsurprised by the depths of depravity some men willingly sink to in order to find gratification, Riley is unprepared for the damage that could be done to the reputation of his own family if he doesn't get to the truth. But at what cost to his personal ambitions...