Away for 7 years, Derringer returns to save his mansion from New Orleans' carpetbagging Reconstruction overlord. Yancy Derringer's former belle Amanda also tells Derringer she posed as his wife to keep the Waverly from rapacious Yankees. The destitute Yancy, who fought for the Confederacy but now champions peaceful reunification, is trailed down the Mississippi by 3 vengeful card cheats. Guarding gentleman adventurer Yancy is his mute friend Pahoo-Ka-Ta-Wah who previously saved the daredevil's life. The Pawnee warrior's deadly with scatter gun and throwing knife, both...
Detonating the world's toughest waterfront is Yancy's secret assignment from the Big Easy's Reconstruction administrator. Against his best enemy, vice lord Toby Cook, owner of the Jumping Jack casino, Yancy hides an explosive trick up his sleeve - the tiny, noble sea captain of a ship crammed with the latest invention from Sweden. Backing up the unlikely duo is the silent, lethal Pahoo.
After overland raiders seize an Army payroll, Yancy's riverboat hauls the next shipment. Complicating Yancy's assignment is Billie Jo James, who's so female her father tried to tone her down with 3 male names. Billie flips her wig over Yancy, but even aboard Yancy's Mississippi queen ensconced in his usual cabin for Southern belles, she keeps throwing herself in Yancy's path and her back-story doesn't hold bilge water. Could she have a brother named Jesse?
When a tombstone & funeral wreath are delivered to Administrator Colton, Yancy has 24 hours to prevent Colton's being killed by the South's ace duelist, Spade Stuart. Colton's in an especially vulnerable situation, because he's absorbed with impressing a beautiful visitor from Boston, who's a friend of his sister.
Madame Francine's girl midget cousin keeps being drug back to a mysterious black freighter from China, The Murphy Brown, supposedly only containing the finest silk. Reconstruction administrator Colton suspects smuggling, but lacks evidence so he assigns Derringer and Pahoo to use not-quite-legal methods to investigate, and to protect the adorable, pug-nosed Irish waif Gidget from being silenced.
New Orleans' underworld conspires to rub out post-Civil War administrator Colton, right when Colton's sister Agatha finally arrives on a visit. Yancy expected a Boston battle-ax, but he's smitten with her charm and wit. Colton has a heavy workload, fending off crime czar Lance Carter, and wowing Agatha with his Reconstruction wizardry, while throwing a blockade between her and Yancy.
Mr. Proctor is shot, and Yancy finds a Confederate half dollar in his dying hand. After traveling by horseback to a plantation mansion in Baton Rouge, Yancy learns of the (supposed) sudden death of General Stafford. However, the General is actually still alive, and his coffin instead contains a horde of $500,000 worth of silver and gold bullion, sent from Richmond (originally intended, evidently, for the production in New Orleans, of Confederate coins). The grand-daughter Gloria is engaged to marry the suspicious Earl Bartley. Yancy looks for clues, but is interrupted...
Colton asks Yancy to investigate counterfeit money that's being passed throughout the French Quarter. His investigation brings him into contact with Lonesome Jackson, a Virginia City miner who recently struck in rich and came to New Orleans seeking a wife. The Treasury Department suspects Jackson because of the large bankroll he's carrying, but Yancy believes that the miner is being set up as a patsy by the real counterfeiters.
Yancy investigates when several shopkeepers along Duquense Street are paid twice as much as their property is worth, and are subsequently robbed and murdered. He learns that a projected railroad spur is to be built to the waterfront through that shopping district and unscrupulous Northerners plan to use illegal means to grab all the available real estate before the project is officially announced.
Derringer is falsely accused of complicity in a waterfront property theft. Administer Colton manages to get Matthew Younger to drop the charges, but Yancy decides the insurance man may be throwing charges around to hide the real perpetrators. His investigations lead him to a waterfront dive and its grave-robbing habitués and ultimately to a midnight assignation in a New Orleans cemetery to gather proof of the insurance scam.
Christmas in New Orleans may not be particularly festive in the Derringer household this year, since Yancy's Uncle Henry Spinner, a government engraver, has been murdered and the plates for the new hundred-dollar greenback he was designing have disappeared. While Yancy searches for the murderer, his old hound-dog Dixie shows up at this family seat along with the news that the dog is the only one who can lead Yancy to where the family treasure is buried. The episode ends with an impromptu Christmas party attended by most of the series' recurring characters.