A voiceover from Darkwing tells us that today, we're in for Something Completely Different: the story of a crimefighting hero from three hundred years ago, the Darkwing Doubloon.
Drake Mallard is a seaman on the galleon of the Royal House of Muddlefoot, which includes King Herb, Queen Binkie, and Princes Tank and Honker. Unbeknownst to the royal family, Drake Mallard has a dual identity as the Darkwing Doubloon, scourge of the seven seas, whom the king fears by reputation. The king would do better to fear Negaduck and his pirate band, consisting of Megavolt, the Liquidator, Quackerjack, and Bushroot (the dynamic among whom is very similar to that among the present day Fearsome Five). The pirates spot the royal galleon and promptly board it; Negaduck is unamused when the king expresses relief that at least he isn't the Darkwing Doubloon, and he and his men loot the ship with only token resistance from Drake. As the king despairs at the theft of his jewels, Drake tricks the royal family into thinking the galleon is sinking, and they sail off in the lifeboat as Drake dons the mantle of the Darkwing Doubloon. He rallies his crew, consisting of historical counterparts of Gosalyn, Launchpad, Stegmutt, and Fenton Crackshell (alias Gizmoduck), asking them to wait for him on the king's ship.
As Negaduck divides the king's jewels between his crew (keeping most for himself), the Darkwing Doubloon boards his ship. After trading insults with his nemesis, Darkwing tricks Negaduck into walking his own plank, but when Negaduck climbs aboard again and refuses to hand over the jewels, Darkwing vanishes in a puff of blue smoke, leaving a gold doubloon which Negaduck takes as a memento of his victory. Back on the king's ship, Darkwing explains that the short confrontation was intended to give Negaduck a false sense of security, and soon his crew have boarded Negaduck's ship while tricking Negaduck's crew into boarding their ship. But after Negaduck corrects this tactical slip-up, Darkwing flees into the captain's cabin, where he finds the king's treasure. Gosalyn has an idea: they can smuggle the jewels back to their ship hidden under their clothes. She hands jewels over to Darkwing, Gizmoduck (who would rather announce the plan first, an objection Gosalyn ignores), Launchpad, and Stegmutt, but the latter is just as careless with his tail as his present day version, and he unwittingly knocks Gosalyn into an empty treasure chest as he turns to leave. Darkwing and the rest of his crew are unaware of her plight as they are thrown overboard with the jewels, and it isn't long before Negaduck discovers that his treasure is gone but Gosalyn is still aboard.
Darkwing checks the recovered treasure against an inventory list, but finally notices Gosalyn's absence, and orders his crew to return to Negaduck's ship. Gosalyn herself is able to fend off Negaduck's crew, but not for long, and that night, Darkwing leads his crew aboard. Unfortunately, stealth is not their strong point, and the rescue mission turns into a ransom handover, with Darkwing reasoning that getting Gosalyn back is more important, and they can get the jewels back later. Unsurprisingly, once Negaduck has the jewels back, he refuses to hand over Gosalyn, and Darkwing is reduced to throwing a tantrum over his defeat. Back on the royal galleon, Launchpad suggests sinking Negaduck's ship, which Darkwing dismisses since Gosalyn and the jewels are still aboard. Instead, he decides they should sink their own ship, luring Negaduck towards them.
Negaduck rants that he and his crew can't make for their island hideout while the Darkwing Doubloon is still on the seas, and Megavolt and Bushroot unthinkingly reveal to Gosalyn that there is a map to the island in Negaduck's cabin under the sextant. As the enraged pirate captain chases his big-mouthed crew around the deck, Gosalyn slips off the ropes binding her and steals the map. Meanwhile, Darkwing's plan is put into action; after the royal galleon fires on Negaduck's ship, Negaduck returns fire, and Darkwing instructs Gizmoduck to begin pumping water onto the ship, causing it to start sinking. As predicted, Negaduck sails toward the ailing galleon, but with Gosalyn tied to the bow as a figurehead. An alarmed Darkwing orders Launchpad to steer the ship away, revealing the trick to Negaduck. Re-grouping, Darkwing (through a misunderstanding) gets Stegmutt to fire him onto Negaduck's ship from a cannon; although he is able to fend off the pirates and untie Gosalyn, Negaduck steers his ship through the royal galleon, splitting it in half and causing the crew to abandon ship.
Gosalyn reveals that she still has the map to Negaduck's hideout, and, using Stegmutt as a raft and the Gizmosuit for propulsion, Darkwing and his crew sail off in pursuit of the Fearsome Five. They arrive at the island ahead of the pirates, and capture Quackerjack, Bushroot, the Liquidator, and Megavolt one by one to leave Negaduck alone in his final confrontation with Darkwing in the cave containing his treasure hoard; although their fight takes place in darkness, Darkwing's crew arrive to find him victorious. The Fearsome Five are thrown into the brig of their own ship, which Drake presents to the royal family as a replacement galleon along with their recovered jewels. King Herb offers to reward Drake for his service; Drake says that serving the royal family is reward enough, but he spots the gold doubloon from his first confrontation with Negaduck lying on the deck, and asks to keep it. The king happily agrees.
This episode contains examples of the following tropes:
- Angrish: Negaduck begins ranting incomprehensibly as he chases Megavolt and Bushroot around the deck for giving away the location of his treasure map in front of Gosalyn.
- Catchphrase: Apparently the historical versions of the Darkwing Duck cast have the same catchphrases as their present day versions. Quackerjack's battle cry is still "It's play time!", Gizmoduck still activates the Gizmo suit with the phrase "Blathering blatherskites!", and Darkwing still mutters "Yep, yep, yep" when he thinks he is in control of a situation.
- Damsel in Distress: Darkwing Doubloon's youngest crew member, Gosalyn is held captive on Negaduck's ship
- Filk Song: As Negaduck's crew carry the king's jewels toward their hideout, Negaduck commands them to sing the song "Pirates are Something to Fear on the Sea", which shares its tune with "Ninety-nine Bottles of Beer on the Wall". Fittingly, the pirates are captured one by one by Darkwing's crew as they sing until only Negaduck remains.
- Flat Joy: After Negaduck's crew succeeds in throwing Darkwing's crew overboard during their second confrontation, Negaduck declares that he has defeated the Darkwing Doubloon once again. Megavolt, Bushroot, Quackerjack, and Liquidator react with an unenthusiastic "Yay."
- Generation Xerox: The 1600s characters have the same dynamic as their modern day versions. Drake/Darkwing is still an egotist and still adoptive father to Gosalyn (who is just as spirited as her modern day counterpart), Launchpad is still his pilot (in the nautical sense), and Stegmutt and Fenton Crackshell are still his allies (though the Gizmosuit has a Spanish conquistador theme in the 1600s). The Muddlefoot family still consists of Herb, Binkie, Tank, and Honker; Herb is still good-natured but not too bright, and Tank still bullies Honker at every opportunity. Negaduck still leads the Fearsome Five and heaps abuse on the other four, Megavolt and the Liquidator still bicker with each other, Bushroot is still a bundle of nerves, and Quackerjack is still an Ax-Crazy goofball.
- I'll Never Tell You What I'm Telling You!: As Negaduck fumes over not being able to hide the king's treasure on their island hideout while the Darkwing Doubloon is at large, Gosalyn is interested to hear about the island. Megavolt reveals that they have a map to the island; just as Negaduck is berating him for giving away the existence of the map, Bushroot joins in and berates Megavolt for almost telling Gosalyn that the map is in Negaduck's cabin under the sextant.
- I Meant to Do That: No matter how many unexpected events seem to get in the way of rescuing Gosalyn and the king's jewels, the Darkwing Doubloon repeatedly insists that it's all part of his master plan.
- Literal-Minded: During the second attempt to rescue Gosalyn from Negaduck's ship, Darkwing tells Stegmutt to launch him (i.e., throw him) onto the other ship like a cannonball. Stegmutt misunderstands and puts Darkwing into a cannon barrel before lighting the fuse, sending him flying through the air.
- Malicious Misnaming: Negaduck addresses the Darkwing Doubloon as "Darkwing Buffoon" during their first confrontation, showing that he finds his good opposite as tiresome as his present day counterpart. When they meet again, he addresses Darkwing as "Baboon"; the offended Darkwing initially corrects him to "Buffoon".
- Offscreen Moment of Awesome: The final confrontation between the Darkwing Doubloon and Negaduck takes place in total darkness, but it is certainly noisy; Darkwing's crewmates arrive to find Negaduck subdued and Darkwing triumphant.
- Oh, Crap!: Megavolt gets this expression on his face after Darkwing magnetises him and he finally contorts his body to avoid being impaled by the flying cutlasses of his crewmates - only to see a cannon skidding across the deck toward him...
- Pretty in Mink: Queen Binkie wears an ermine-trimmed robe as part of her royal regalia.
- Self-Serving Memory: The Darkwing Doubloon's account of his first meeting with Negaduck is exaggerated to portray him in a more heroic light, with Darkwing describing their (actually very short and simple) fight in melodramatic terms.
- Something Completely Different: Darkwing's narration mentions this trope by name as he introduces the story of his swashbuckling ancestor, the Darkwing Doubloon.
- With Catlike Tread: As they attempt to rescue Gosalyn from Negaduck's ship, Darkwing emphasises the need for silence to his crew. Unfortunately, the noise of the Gizmosuit and Stegmutt yelling "Smash! Smash! Sit on 'em!" before falling on Darkwing and Gizmoduck and squashing them flat is more than enough to alert Negaduck's crew.