After losing their boathouse in an accident, Donald Duck reluctantly agrees to take his nephews to visit their grand-uncle Scrooge McDuck. Enthralled by the wonders of the McDuck Manor, the triplets investigate family secrets.
Scrooge seeks to teach Louie the value of a days work but Louie ends up losing Scrooge's #1 dime. Meanwhile, Dewey and Webby get caught up in a conspiracy.
Webbigail meets a mysterious new friend called Lena, when one night she and the boys accidentally crash the Beagle clan get-together for Ma Beagle's birthday party.
After watching a scary movie about evil doubles, the kids decide to explore an eerie abandoned subway tunnel in search of the mythical underground-dwelling Terra-Firmians. Also, Launchpad becomes paranoid that Louie is an evil double.
At a mysterious casino resort in Macaw, China, Donald competes with his cousin and luckiest person alive, Gladstone Gander, to impress Louie. Meanwhile, Scrooge tries to lure the kids away from the resort's strangely endless distractions..
Huey competes with Dewey for a coveted internship with Duckburg's newest tech billionaire, Mark Beaks, while Scrooge and Glomgold team up to take this new competitor down. Also, a hired goon arrives to steal Beaks' secret project.
When Webby locates an artifact that may lead the boys to their missing mother, the spiteful Greek god Zeus, tired of always losing against Scrooge, forces the entire Duck family to compete in a fixed match against his hero son, Storkules.
Launchpad must defeat Mark Beaks' new robot chauffeurs in a race to keep his job as Scrooge's driver, but Gyro and Fenton realize that something is dangerously wrong with this new technology.
It's Scrooge's birthday, so the nephews try to make him a party better than those of his beloved late butler, Duckworth, by inviting only his greatest enemies. When Scrooge disappears at the party, the nephews suspect everyone there.
Dewey invents a holiday that allows the triplets to be only children for a day, so each of them picks a dream activity to enjoy on their own only to end up being overwhelmed by it.
Magica De Spell is close to exacting revenge on Scrooge, so the family races against time to plan a dangerous rescue mission to save Scrooge and the city.