Tessie and Finn want nothing more than to sail across the Atlantic and start their lives fresh in Boston.
But before they do, they must save a woman who doesn't want to be saved.
Charged with the impossible task of convincing her mother, the Black Bonnet, to step aside or accept her fate, Tessie and Finn are drawn into the battle raging for Dublin's underground.
While Tessie tries to force her mother's hand, and Finn and Mickey confront the ghosts of Dublin's past, a deadly showdown between the Angel of Bishopsgate and the Black Bonnet brews on the horizon.
Can Tessie and Finn survive the inevitable clash of foes, or will Dublin's murky clutches drag them ever deeper and further from their dream?