"Cap'n Drakken" is the seventy-eighth episode of Kim Possible.
Kim and the other seniors go on a trip to a historical seaport run by Barkin's father. There, they lose all electronics such as cellphones for a week. They have to work as they did back in ye olden day; for example: making horseshoes, churning butter, and getting eggs. Meanwhile, Dr. Drakken is possessed by Black-Eye Brown after opening a sea-buried treasure chest.
The episode begins outside of Middleton High School where the seniors are getting ready for their senior trip to South Beach Bay Harbor (with Kim noticing a visibly-packed Ron with a small pack contained with his clothes and a larger pack containing various MP3-compatible music for the trip in his "Roadside Pack"), to which Mr. Barkin announces the trip has been canceled due to a volcanic eruption, much to the dismay of the students. Barkin then announces the students will be taking a senior trip after all... to Fort Mystic Cove Haven, which is a living re-enactment of 18th century-America, for a week. The students start to groan about the change until Barkin announces they will be graded on their trip.
The students arrive at Fort Mystic Cove Haven to see who's in charge of the place: Franklin Barkin, father to Mr. Barkin! Barkin Sr. announces to the students they'll be living as if they were back in the 18th-century, which means surrendering anything that doesn't belong in the colonial era (i.e., electronics). Barkin Sr.'s parrot companion, Remy, notices Ron putting his smaller pack on the wagon for the electronics as a decoy and uncovering the bush-disguised "Roadside Pack" nearby, with Rufus attempting to chase Remy away, much to Ron's chagrin. As Kim questions Bonnie why she has to complain, she tells Kim someone has to complain about the trip after complaining about having to write letters to communicate with others; Bonnie points out that they aren't being graded on attitude until Barkin Sr. point out attitude is among one of MANY things the students are being graded upon. Barkin Sr. deducts two of Bonnie's points for her attitude, as well as two of Ron's points for "language" and because Ron did not speak in 18th-century talk. As Barkin Sr. notices how Kim, Ron, Bonnie, and Monique clean up nicely after donning colonial wear (to which Bonnie retorts the outfits would look better on Halloween), he gives the four of them scrolls containing what they have to do throughout the week. Ron shows up to his blacksmith's apprenticeship, only to find he's apprenticing to Barkin Sr. who's filling in for Mr. Littleton, the town's blacksmith, who's out from "ye old branding incident." Kim is shown a butter churner and questions the woman who is overseeing her chore for the day, only to discover Barkin Sr., in a gown and bonnet, filling in for her master. Barkin Sr. shows Kim how to churn milk to turn it into butter. Barkin Sr. hands Bonnie a basket to collect eggs from chickens, to which Bonnie complains why she couldn't get eggs like "the rest of the world does," which is through the internet. Bonnie reluctantly agrees to collect eggs after her rant.
Dr. Drakken and Shego are shown in his new underwater lair, with Shego questioning why he has to have his new lair under the sea; Dr. Drakken (with Shego mocking him) claims it's a perfect place for his new "doom ray" (which Dr. Drakken has no clue as to what it will do). Dr. Drakken was informed something was blocking a tube that was sucking water up, claiming it to be an "actual dilemma" because no henchmen were stuck in the tube. The tube was emptied inside the lair, on top of Dr. Drakken himself.
Back to Fort Mystic Cove Haven, Barkin Sr. checks on the students to see what they're doing. Kim and Bonnie are visibly annoyed with their chores and Barkin Sr. deducts points from the two of them; he later deducts points from Ron on his lousy handiwork on forging horseshoes. At the end of the day, the students (with the exception of Ron and Rufus "watching TV" on a bucket of fireflies) gather around the fire to listen to Barkin Sr. regaling a tale of how the town fought to preserve its history for centuries. After hearing the word "pirates," Ron and Rufus join the others, claiming he was "watching re-runs." Kim deduces, after hearing about Black-Eye Brown and his parrot Roger, that Remy is descended from Black-Eye Brown's feathered companion, being a 5th generation descendant.
Meanwhile, back in Dr. Drakken's underwater lair, Dr. Drakken's henchmen bring a vacuum tube to suck the sand that buried Dr. Drakken. As Dr. Drakken is about to lash out at his henchmen about burying him, Shego notices a treasure chest next to him, immediately catching his attention. Shego isn't too thrilled with Dr. Drakken opening the treasure chest, pointing out the skull (with glowing eyes) and crossbones, to which he dismisses her warning, reassuring her of his lack of concern for warning labels. As soon as Dr. Drakken opens the chest, a cloud of black smoke with glowing red eyes charges onto Dr. Drakken and he soon gets possessed by the pirate, Black-Eye Brown, leaving Shego visibly confused to Dr. Drakken's changing moods.
The new day begins and Barkin Sr. notices Ron forging perfect horseshoes until Remy catches Ron cheating by exposing Rufus for forging the perfect horseshoes. Kim notices Ron trying to touch a hanging cage he noticed while the students arrived to Fort Mystic Cove Haven and pointed out the "DO NOT TOUCH" sign on it. Kim shows Ron her handiwork from the day before: a small cube of butter. Kim and Ron notice Bonnie lugging buckets of water on her shoulder, claiming she left egg collecting because of "creative differences." As Bonnie taunts Ron with a fire he started while smithing, Kim smirkingly tells Bonnie to be careful about what she says by telling her what the town does to witches, to which Bonnie frightfully flees. Not too long afterward, Wade shows up, also in colonial-era clothing, on horseback. Ron, thinking Wade built a robot horse, tries to find his horse's "control panel," only to be comedically kicked away by the horse. Wade informs Kim and Ron of Dr. Drakken's new undersea lair off the coast of Fort Mystic Cove Haven. Kim, Ron, and Wade arrive to the port to catch a ride to find Dr. Drakken, only to be caught by Remy, who is subsequently caught by Kim in a net, holding him hostage. Kim and Ron dive into the ocean to look for Dr. Drakken, leaving Rufus to guard the yacht and Remy the prisoner.
Below in the lair, Shego tells Dr. Drakken she found a buyer for the treasure only to be interacting with a possessed Dr. Drakken. Shego sends a quip to Dr. Drakken about his sudden pirate look only to get a response back from Dr. Drakken himself, claiming he felt like bringing out his inner pirate. Kim and Ron confront Dr. Drakken, only for Dr. Drakken to speak as the pirate once again, leaving Kim and Ron visibly confused. As Shego is about to fire her power at Kim, she points out to Shego that one blast from her would destroy the lair, which Dr. Drakken agrees to, and Shego halts her powers; Ron outsmarts both Shego and Dr. Drakken by cracking the lair's glass window with a pickaxe. Dr. Drakken (between his and Black-Eye Brown's personalities) and Shego escape the flooded lair, with Shego carrying the treasure chest out of the lair.
Back on the yacht, Rufus takes a snooze while Remy cuts his way out of the net with his beak, escaping and flying to Dr. Drakken/Black-Eye Brown's shoulder. Dr. Drakken/Black-Eye Brown orders Shego to hoist the mainsail and calls her a wench, leaving Shego visibly irate and threatening to plan a funeral at sea, scaring the possessed Dr. Drakken. Ron and Kim are greeted by Rufus with drinks and towels only for the three to discover that Remy escaped while Rufus was asleep.
En route to the shore, Shego becomes visibly annoyed from Dr. Drakken's pirate talk (taking her anger out on Remy by firing a fireball at him, stating "Hey, one birdbrain ordering me around is enough!" After listening to Dr. Drakken telling her to stick to the code for pirate talking, thanks to Remy, Shego decides to look up who Black-Eye Brown is on the hovership's database. Shego discovers that Black-Eye Brown, currently possessing Dr. Drakken, is in pursuit of his magical silver cutlass inside the lighthouse of Fort Mystic Cove Haven.
- This is the only episode where Dr. Drakken was seen with bulky fingers, like most boys/men in the series, instead of skinny ones like most girls/women in the series.
- Black-Eye Brown may be an ancestor to Dr. Drakken; strangely, as Shego looks up Black-Eye Brown on the hovership's database, Black-Eye Brown's picture looks almost identical to Dr. Drakken.
- Unlike most cases where a character gets possessed by something else, Dr. Drakken partially retains his personality as well as gaining Black-Eye Brown's personality.
- Franklin Barkin keeps substituting for everyone else, just like his son does.
- Franklin Barkin changing jobs and hats, including bonnets.
- Franklin Barkin deducting points.
- Black-Eye Brown may be an allusion to Blackbeard.
- South Beach Bay Harbor may be an allusion to South Beach Harbor in San Francisco, CA.
- Ron asks about The Jolly Roger, which was the boat owned by Captain Hook.