Donald Duck reluctantly leaves his triplet nephews, Huey, Dewey and Louie, with his estranged uncle Scrooge McDuck while he goes to a job interview. After Scrooge locks the triplets in a room for making fun of him, they come across Webby Vanderquack, who befriends them and shows off a collection of relics that Scrooge and Donald collected while adventuring, only to accidentally release various ancient evils housed in them. After the kids help him contain them, Scrooge finds his thirst for adventure rekindled and decides to take them all, along with his driver and pilot Launchpad McQuack, to find the Lost Jewel of Atlantis. However, the group are unaware that Scrooge’s rival, Flintheart Glomgold, seeks the jewel too and has hired Donald as his sailor, leading to a race against time to claim the relic. During their quest, Dewey confronts Scrooge about locking him and his brothers up and not wanting them around, though they later reconcile. In the end, Scrooge gets the Jewel and Donald and the triplets move into McDuck Manor after an accident costs them their houseboat. Revisiting Scrooge’s collection, Dewey discovers a painting of Scrooge, Donald, and the triplets’ long-lost mother and Donald’s twin sister, Della.