Summer 1904. Katharine and her best friend from Oberlin College, Margaret Goodwin Meacham, are thrilled to attend the St. Louis Exposition in St. Louis, Missouri, for the centennial celebration of the Louisiana Purchase. Not only is it a grand, international event, it's also the first time the young women have seen each other in quite a while, and they are giddy with excitement--despite warnings from Katharine's old family friend, poet Paul Laurence Dunbar, to be careful of the fair's less seemly side.

Undaunted, the girls have a lovely time--until the exposition turns from a girls' trip to a misadventure when Katharine stumbles upon a woman in distress. It's obvious that she has been attacked. Katharine does her best to save her, but tragically, before help can arrive, the woman dies. Yet just before her last breath, she utters the words aeronautics competition. . . . Katharine's brothers Wilbur and Orville were asked to enter the competition with their successful 1903 flyer but declined. Katharine wonders how this young woman could be connected to such a prestigious event.

Now, unable to get the woman's face out of her mind, Katharine convinces Margaret to join her investigation--and it's soon clear that the race to be declared the first in flight might just be the deadliest competition of them all . . .