During the Civil War, Jeanne Beaufort becomes a secret agent for the South, seeking to avenge the deaths of her father and brother. While spying on a group of Northern agents, she is captured and forced to marry a man wearing a mask, who has a distinctive tattoo on his wrist. Jeanne escapes and continues her work in Washington D.C. with the help of Henry Morgan, who is also a Northern agent. In Washington, she falls in love with John Armitage, a Northerner. When her identity is discovered, she is forced to flee to Richmond. Morgan, who is revealed to be Jeanne's masked husband, is killed in a struggle with Parson John Kennedy. Richmond is set on fire, but John rescues Jeanne and they marry after the war, despite their opposing sides.