* In 1887 Government inspectors were sent to explore the horrifying - often lethal - living conditions of the Old Nichol, a notorious 15-acre slum in London's East End.
* Among much else they found that the rotting 100-year-old houses were some of the most lucrative properties in the capital for their absent slumlords. Peers of the Realm, local politicians, churchmen and lawyers were making profits on these death-traps of as much as 150 per cent per annum.
* Before long, the Old Nichol became a focus of public attention. Journalists, the clergy, charity workers and others condemned its 6,000 inhabitants for their drunkenness and criminality. The solution to this 'problem' lay in internment camps, said some, or forced emigration - even policies designed to prevent breeding.
* Concentrating on the last fifteen years of the nineteenth century, The Blackest Streets is set in a turbulent period in London's history, when revolution was very much in the air - when unemployment, agricultural depression and a crackdown on parish relief provided a breeding ground for Communists and Anarchists.
* Author of the prize-winning The Italian Boy, Sarah Wise explores the real lives behind the statistics - the woodworkers, fish smokers, street hawkers and many more. She excavates the Old Nichol from the ruins of history, laying bare the social and political conditions that created and sustained this black hole which lay at the very heart of the Empire.