The story of Sarah Emma Edmonds, who masqueraded as a man named Frank Thompson during the Civil War. Among her many adventures, she was a nurse on the battlefield and a spy for the Union Army, and was captured by (and escaped from) the Confederates. The novel is narrated by Sarah, offering readers an in-depth look not only at the Civil War but also at her journey to self-discovery as she grapples with living a lie and falling in love with one of her fellow soldiers.