When a child's body is discovered in tumultuous eighteenth-century London, a struggling writer dares to defy her time and become an unlikely force for social justice in a new historical mystery by Pulitzer Prize-winning author Julia Keller.

Brilliant—but broke. Ahead of her time—but behind on her rent.

Such is the plight of Sarah Fielding in 1750 London, shortly before the opening of Westminster Bridge. Sister of the famous author Henry Fielding, Sarah is a writer as well—but with barely a smidgen of Henry's commercial success. When the body of a young girl turns up on the shiny new bridge, Sarah finds her destiny as a self-described Avenger of Misfortune—the word "detective" was yet to be coined—in the churning, volatile, but alluring world of Georgian London.

As the great city's population surges, inequality sharpens its claws. Wealth protects the powerful, while a burgeoning underclass is left voiceless and vulnerable. Joining forces with the Bow Street Runners, the nation's first professional police force, Sarah plunges headlong into a case that will expose this stark divide between rich and poor—and dares to expose an evil secret that lurks within the glamorous, perilous city.