Scrooge reteams with his conniving ex-partner and old flame, Goldie O'Gilt, to find a long-lost golden lagoon, but Glomgold has other plans.
Scrooge McDuck, Huey, Dewey, and Louie attend the opening of the new "Glomgold Wing" at the Natural History Museum, hosted by Flintheart Glomgold, depicting the meager earnings Glomgold received against Scrooge. While scavenging the banquet food, Scrooge runs into Goldie O'Gilt attending the gala. Scrooge suspects Goldie is always out for something. His suspicions come true once Glomgold unveils the wing's newest exhibit — a Yukon mammoth skeleton — and Goldie disappears with its skull.
Scrooge immediately rushes back with the boys to McDuck Manor. He explains that during the Gold Rush, he helped Goldie search for the Golden Lagoon of White Agony Plains but Goldie tried to steal the map from Scrooge. They came across the mammoth where Goldie lost one half of the map to the mammoth before the two jumped into the water, where they were frozen together for five years. When the mammoth was discovered by Glomgold, Goldie came to get the map back. The group returns home where Goldie is already waiting. Before Goldie realizes the other half of the map is in Scrooge's hat, Scrooge wrestles it back from her. Goldie proposes they work together to find the Golden Lagoon and Scrooge reluctantly agrees.
At the Yukon, Scrooge and Goldie embark to White Agony Cave, unaware they are being followed by Glomgold. Goldie soon threatens Scrooge with gunpowder she set up leaving her with the map. However, the gunpowder is put out by a bear Scrooge tames and he stops Goldie in her tracks. Scrooge and a tied-up Goldie finally approach the Golden Lagoon but find a dead end. When Goldie recognizes he has a grudge, Scrooge admits that being trapped in that iceberg helped him forego his anger when they grew feelings for each other, but when Goldie thawed out, she still abandoned Scrooge in the glacier. After Goldie helps Scrooge reconcile his grudge, the two then discover the Lagoon is on the other side of the cavern. But Glomgold appears to reveal he and Goldie are working together to find the Lagoon.
Scrooge duels Goldie with pickaxes until Glomgold throws a shovel to a rock above the two. Before the rock comes down, Goldie pushes Scrooge out of the way and falls into the molten gold. Scrooge is knocked out by Glomgold who ties him to a derrick, intending to kill Scrooge with liquid gold. However, Goldie survives and escapes from the gold to rearrange the gold pipeline into a cargo ship tank she absconds on, leaving Glomgold betrayed and Scrooge delighted.
Scrooge returns to the manor where, upon finding his top hat, he uncovers a package and note from Goldie offering to go treasure-hunting together next time.
- David Tennant as Scrooge McDuck
- Danny Pudi as Huey Duck
- Ben Schwartz as Dewey Duck
- Bobby Moynihan as Louie Duck
- Toks Olagundoye as Bentina Beakley
- Keith Ferguson as Flintheart Glomgold
- Allison Janney as Goldie O'Gilt
- Although Launchpad McQuack and Webby are present, neither speak in this episode, ergo making it the first episode where one or a six main characters doesn't have a single line of dialogue.
- Scrooge and Goldie mention a captain named Foghorn, who was a character who served as a temporary employee of Scrooge on two separate occasions.
- It is revealed that Scrooge and Goldie's youthful figures are due to participating in time-altering misadventures, i.e. Scrooge was stuck in a timeless dimension for some time and Goldie used a fountain of youth.
- Scrooge was still alive during the Gold Rush, albeit as a young adult.
- Goldie mentions that the fountain of youth she used was in the country of Ronguay, a reference to the country seen in the original series's pilot episode, "The Treasure of the Golden Sun."