History Detectives investigates the story of a mystery hero, and a letter recently unearthed by his widow and daughter. Tukufu Zuberi sets out to find the author of a book printed in 1939 titled "Diana: A Strange Autobiography". It tells a sympathetic story of how one woman discovers that she is a lesbian. An Oregon man believes he owns a watercolor painted by a soldier in Rock Island, Illinois during the Civil War. Wes Cowan travels to Chattanooga, Tennessee to learn more about the crucial battle over a strategic vantage point, Lookout Mountain.