Chicago, 1898. Rough-around-the-edges Harriet Morrow has long been drawn to the idea of whizzing around the city on her bicycle as a professional detective, solving crimes for a living without having to take a husband. Just twenty-one with a younger brother to support, she seizes the chance when the prestigious Prescott Agency hires her as its first woman operative. The move sparks controversy -- with skeptical male colleagues, a high-strung office secretary, and her boss, Mr. Theodore Prescott, all waiting for her to unravel under the pressure ... Only an hour into the job, Harriet has an assignment: Discover the whereabouts of a missing maid from one of the most extravagant mansions on Prairie Avenue. Owner Pearl Bartlett has a reputation for sending operatives on wild goose chases around her grand estate, but Harriet believes the stunningly beautiful Agnes Wozniak has indeed vanished under mysterious circumstances -- possibly a victim of kidnapping, possibly a victim of something worse ... With Mr. Prescott pushing a hard deadline, Harriet's burgeoning career depends on working through a labyrinth of eccentric characters and murky motives in a race to discover who made Agnes disappear. When her search leads to Chicago's Polish community and a new friendship in Agnes's charming older sister, Barbara, clues scattered across the city slowly reveal just how much depends on Harriet's inexperienced investigation for answers ... and the deep danger that awaits once she learns the truth.