From childhood, Susan Gray and her cousin Louisa May Alcott have shared a safe, insular world of outdoor adventures and grand amateur theater -- a world that begins to evaporate with the outbreak of the Civil War. Frustrated with sewing uniforms and wrapping bandages, the two women journey to Washington, D.C.'s Union Hospital to volunteer as nurses. Nothing has prepared them for the horrors of this grueling experience. There they meet the remarkable Clara Barton -- the legendary Angel of the Battlefield -- and she becomes their idol and mentor. Soon one wounded soldier begins to captivate and puzzle them all -- a man who claims to be a blacksmith, but whose appearance and sharp intelligence suggest he might not be who he says he is.

Through the Civil War and its chaotic aftermath to the apex of Louisa's fame as the author of Little Women and Lincoln's appointment of Clara to the job of finding and naming the war's missing and dead, this novel is ultimately the story of friendship between women -- women who broke the mold society set for them, while still reckoning with betrayal, love, and forgiveness.