Von Drake's Superhero Machine turns Dewey into supersmart, psychokinetic Brainboy, Louie into superstrong Captain Muscle and Huey into the "Really Incredibly Fast Guy". But Donald is turned by mistake into supervillain, the Duck of Doom.
Mad scientist Horton Lautrec creates a devolution machine that can turn every living thing into their prehistoric ancestor and bring back the stone age. The machine turns Daisy's pet iguana, Knuckles, into a Godzilla-like giant lizard.
Daisy is sent to do a report on Quintinia, a modern day medieval kingdom, and Donald drives her there. The locals recognize Donald and declare him their long lost king. Evil prince Gaylord tries to assassinate Donald and take the throne.
Donald's been discharged from the navy a day too early, so he returns to serve out one more day on an aircraft carrier. When his dogfighting video game takes over the ship and starts war games, only Donald's gaming skills can stop it.
The fourth Columbo's ship called Snooky holds the priceless jeweled key of Carpathia and only Daisy and her TV crew can see it. Master thief Nigel Nightshade tries to trick her cameraman Donald and get the key. The nephews recognize him.
Daisy interviews egotistical car racing champ, the Rocket. He hits on her, so jealous Donald decides to race against him. The nephews even get him some of Von Drake's potent rocket fuel, but things don't go as planned.
Mad lab assistant Tovar, who loves germs and wants to save them from medicine, uses his invention, the Germinator, to miniaturize himself and help the germs take over Donald's body. The nephews miniaturize themselves and go after Tovar.
In order to justify being late for work again, Donald comes up with an epic tale of heroism that includes mail delivery, outsmarting a dinosaur and even an alien invasion. And it all happened to him that very morning.
Donald's nephews discover incredibly tasty and addictive green goo and become filthy rich overnight by selling it as food. Greed, apathy and egotism quickly consume them. But then, the goo turns into a giant, rampaging monster.
The nephews send the tapes of Donald being the butt of their pranks to the Funniest Home Videos and he becomes an overnight sensation. The sleazy producers decide to raise the stakes by putting gullible Donald in real danger.
The elephant-looking aliens from "The Late Donald Duck" return seeking vengeance against Donald. The nephews use the Superhero Machine from "The Really Mighty Ducks" to regain their powers and try to save him.
While Donald and his nephews are fishing on the river, Daisy goes to see a nearby castle. She meets a strange, slightly unhinged, yet well-meaning nobleman called Gil, who's obsessed with making his depressed giant pet koi fish happy.
While recklessly playing his nephews' fun virtual reality game, Donald ends up wrecking both it and his apartment. He cowardly blames it on a thief he made up. Dangerous criminal, Claw, who happens to match his description, seeks revenge.
Daisy takes Donald and the nephews to the desert to investigate a secret science facility run by Dr. Emil who found a way to recombine molecules and has a bone to pick with Daisy. Meanwhile, the nephews' sibling rivalry escalates.
Paranoid Donald believes that his new neighbors, a nice suburban family that always insists on behaving as normally as possible, are dangerous criminals. The nephews fall for the neighbors' rebellious daughter and discover the truth.
Donald takes Daisy and the kids to find the fabled Nirvana Valley, since Daisy has to make a news piece on it. What they find is a cranky, unfriendly hermit. Dewey, bullied by his brothers, tries to move in with him.
The nephews prank Donald by giving him a strange potion that turns him into his original 1934 version from The Wise Little Hen short. He pranks the kids back and even steals their dates. However, he can't stop aging backwards.
Huey wants to enter a cool teen contest, so wants to look his very best. But when he goes to the dentist to get his teeth whitened, he's outfitted with what he believes to be braces, but it is in reality a special mind-control device intended for someone else and the mastermind will stop at nothing to get it back.
The nephews use Ludwig Von Drake's earthquake machine to convince Donald to finance their contingency plan in case of a quake that just happens to include a top notch clubhouse. Donald realizes he's been had and plans revenge.
The Claw is reformed through hypnosis and released from prison. He tries to do good, but the nephews use his trigger word "gold" to turn him back into his old self and use him to dig for gold for them in a mine that Daisy is reporting on.
Louie rescues some pug-duddies, cute forest animals with the body of a raccoon and the beak of a duck, from poachers. Daisy shoots a piece about the endangered species. The poachers return, so Louie asks his eco-warrior idol for help.
Donald becomes insanely jealous and starts seeing rivals in anyone Daisy comes in contact with including his own nephews. He becomes convinced that in order to win her love back, he must win a snow race.
Donald's slacker cousin Mel Mallard invites him and the kids to his shabby house in Hawaii. He takes Donald fishing while Huey takes over Mel's P.I. business for a day. A missing pencil leads him to a villainess and her superweapon.
Donald takes in a cute little Swiss girl called Helga through cultural exchange program. She turns out to be a psychopath. In Switzerland, the nephews stay with her stereotypically Swiss dad but a shapeshifting alien invader replaces him.
Donald makes the kids join him on a wilderness hiking challenge. The kids meet their friend Gustav Goose there and fall for cute photographer, Suzie, while Donald deals with an overly competitive macho woodsman, Beef Jerky.
The nephews' favorite fast food diner owner Gwumpki is going back to Europe to be the cook for the queen of his country of birth, Bladismokia. Once there, a villain tries to get him to open the cave that holds a legendary orb.
Donald and the kids end up in a haunted mansion instead of the house where a Halloween party is being held. Louie pulls several ghost pranks scaring everyone, but when the real monsters show up, he becomes the boy who cried wolf.
Donald and the kids are with Daisy, who's doing a story in the bayou on a missing gator population. Her investigation leads them to a paramilitary outfit led by a man known as the Colonel. Also, a female gator falls for Donald.
Dewey investigates who stole his favorite comic book and discovers a supervillain who lives in the sewers, hates the surfacedwellers and plans to set the world on fire with his giant lens. Meanwhile, Donald can't relax from all the noise.
Donald becomes paranoid that the kids have become juvenile delinquents. After seeing an infomercial about a special kit that helps parents track their kids, he immediately buys it and begins his investigation.
The kids make a mess while watching a VHS of Ninja Lumberjacks. They end up washing Daisy's news van as punishment. Suddenly, the priceless Cabbage diamond teleports there. They believe an art thief is behind it.
Donald's bug zapper gets stolen. This makes him so paranoid that he doesn't even trust the neighborhood watchdog group called Nosy Neighbors anymore. With the help of his eager nephews, he arms himself to the teeth.
Louie gets Daisy to ask his idol, Aussie adventurer and TV personality Backwater Jack, to take them on his next treasure-seeking adventure. However, he's not what he seems. Also, the villain from Recipe for Adventure returns.
Daisy tries to interview famous animal trainer and Huey's personal idol, Andre, but he turns out to be quite unfriendly. They kids realize that his army of trained house and wild cats are helping him hide something.
The kids want to watch American Gladiators-type champ Flint Steel in action, instead of playing house hockey with Donald. Donald decides to challenge Flint in an attempt to replace Flint as his nephew's favorite hero.
Donald's boos allows Donald to be the captain of his yacht for the weekend. The nephews join him on board. The boat crashes during a storm and they end up on an island, where a mysterious captain is looking for treasure.
Donald and the kids are with Daisy, who's reporting from Africa on the local wildlife. Her pompous colleague, Kent Powers, is also there. He decides to impress the viewers with spectacular stunts and hires a gorilla to do them for him.
Donald, Daisy and the kids are in a museum in China to do a report on the famous statues of Terracotta Army. Huey falls for a mystical local girl, Soo Ling, who works in the museum and is not what she seems.