When Donald Duck decides to join the US Navy, he enlists his uncle Scrooge McDuck to look after his nephews, Huey, Dewey, and Louie. Although reluctant to do so due to their hyperactivity, along with his continual pursuit of increasing his wealth and maintaining harsh business ethics, he eventually warms to them upon seeing how smart and resourceful they are, and takes them into his manor as well as a number of adventures. In addition to them, the show features frequent appearances by Gyro Gearloose, an established comic book character, as well as guest appearances by Donald in the first season – this was either a full appearance, or in a cameo scene when Scrooge and his nephews read letters he sends to them, and a few minor appearances by Scrooge’s old flame, Glittering Goldie, whose character was adapted from the comic books.
The show introduced new characters to the Duck universe; while some were minor including: the nanny Mrs. Beakley, whom Scrooge hires to babysit the nephews; Mrs. Beakley’s granddaughter Webby; Scrooge’s pilot Launchpad McQuack; Doofus Drake, an admirer of Launchpad and a close friend of the nephews; and the McDuck Manor butler, Duckworth. The second season later introduced three new additional characters as part of the show’s stories: “Caveduck” Bubba Duck and his pet triceratops Tootsie; and Fenton Crackshell, Scrooge’s personal accountant who secretly works as a superhero named Gizmoduck.