Hoping to shift the balance of power in the United States' Civil War, the League of Darkness heads across the Atlantic in the Prometheus while being pursued by the crew of the Aurora. When the Aurora crashes, Phileas, Rebecca, Jules, and Passepartout are welcomed into the home of a true Southern belle, Saratoga Browne. Passepartout and Rebecca join forces with the Union to try and defeat the Prometheus, while Phileas and Jules go after the airship and Count Gregory, who kidnaps Saratoga to force Phileas' hand. Jules and Phileas try to manage a daring rescue but Count ...