London, 1885. Anna Kronberg hides in the city's most notorious slum, offering medical treatment to prostitutes, beggars, and criminals of all kinds. None of her neighbors knows her true identity, and she makes sure it stays that way. When the Irish thief Garret O'Hare breaks into her home in the dead of the night, bleeding profusely from a gunshot wound and collapsing on her bed, her life begins to take a deadly turn.