Jack the Ripper may be fading into memory, but east London has found no peace. An investigation into the assault of a policeman leads DI Reid and the men of H-Division to the newly-emergent Chinatown, where Jackson discovers evidence of a new and devastatingly powerful opiate. Reid fears a new kind of hell is to be released onto his streets.

A young woman is found murdered at the London Hospital and the only clue to her identity is an unusual deformity. The hunt for her killer takes Reid and the team into the shadowy netherworld of the freakshows, where they must seek the help of Joseph Merrick, aka the Elephant Man. Reinforcements for H-Division arrive in the form of DC Albert Flight.

The abduction of a prominent member of the London County Council introduces Reid to Councilor Jane Cobden, the first woman appointed to the LCC - because it appears the kidnappers are radical supporters of Cobden's aims. Long Susan is taken by force to the gang's hideout, and she soon finds herself growing sympathetic to her captors' lives and aims.

An Irish bomber is sprung from prison and barely a day later a prominent opponent of the Home Rule movement is murdered. Chief Inspector Abberline is convinced that the Irish Republican Brotherhood is active once more and orders Reid to send the Irish DC Flight undercover into Whitechapel's Irish community.

An investigation into the brutal murder of a Telegraph Boy reveal a vice racket being run from the offices of the GPO. A ledger leads Reid to the centre of the one of London’s most august financial institutions, Barings Bank.

Churches and synagogues are being burnt and desecrated in Whitechapel and Reid suspects the same hand behind the various attacks. Meanwhile, the all-too-brief domestic happiness that Sergeant Drake has enjoyed is disrupted by the arrival of a friend from his wife Bella's past, the mysterious and charismatic scholar, Gabriel Cain.

A valuable symbol of the British Empire’s wealth shows up in the form of an uncut diamond. It is a jewel ‘freed’ from the diamond monopoly of De Graal by one Daniel Judge, Captain Jackson’s untrustworthy older brother. Reid and Flight find themselves being drawn to the plight of a local craftsman defrauded of his work and income by a scam that is set to return H Division to the malign influence of Detective Inspector Jedediah Shine.