Victorian London: slums and stucco, strict morals and dark secrets.
The sex trade in vulnerable young inglish girls was booming, fuelled by las laws and lucrative trafficking to the brothels of Paris and Brussels.
Chelsea's most exclusive establishment counted cabinet members and royalty amongst its clientele.
In the searing summer of 1885, the situation hit the headlines.
There were arrests, riots, a tabloid scandal and a sensational trial - and one man lit the touchpaper. He was Jeremiah Minahan, Irish ex-inspector, exposer of corruption, rebel with a cause.
This is his extraordinary story, and that of the women he helped to protect. It is a very Victorian scandal, but also, a tale for our time.