New York, 1891: a rapidly changing city, torn between lamplight and electric light, where the burgeoning steel and railway industries attract a flood of humanity from every corner of the globe, fuelling cut-throat gangs, corruption and vice.

A prostitute is found brutally murdered. Immediately fear starts to spread. The victim bears the same hallmarks as Jack the Ripper's recent killing spree in England. Could it be that the Ripper has crossed the Atlantic to fresh killing grounds? Or is this simply a copycat murder?

To solve the case, one of the original English Ripper pathologists, Finley Jameson, is teamed up with Joseph Argenti, one of the new 'untouchable' detectives, hand-picked by a New York Mayor eager to fight corruption.

But Michael Tierney, the city's leading gangster, has his own ideas about how the city should be run. And as the body-count rises, and Jameson & Argenti are taunted by the killer in open letters, they find themselves fighting not just to save the next victim, but for the city's very soul.