Donald is dragged into a feud between Scrooge and Zeus, while Dewey and Webby search for an artifact that may provide the truth about Dewey's mother.
After their plane gets caught in a storm, the McDucks land on an island off the coast of Greece. Consulting his guidebook, Huey recognizes they are on the mythical island of Ithaquack, the home of legendary Greek gods and heroes. Donald Duck and Scrooge McDuck suddenly become anxious and urge everyone to leave immediately until they are then greeted by Storkules, the Greek demigod hero. Storkules delights in seeing the McDucks again, especially Donald, who is less than enthusiastic. Then, Storkules' father, Zeus, manifests after sensing that Scrooge is on the island. Huey and Louie inquire why Zeus is angry at Scrooge and how the god knows their family. Zeus explains that Scrooge, Donald, and Della Duck came to Ithaquack years ago and were welcomed by the gods. However, Scrooge's popularity and ability to beat Zeus in every challenge led Zeus to banish his family, while the other gods and inhabitants left the island when Scrooge was forced out (although Zeus' wrath was another factor that led to Ithaquack's desertion). This time around, Scrooge and Donald don't want any trouble, as their plane is in need of repair and promise to leave once it is fixed. Storkules proposes to let the McDucks stay for a while as guests, which Zeus begrudgingly agrees to.
While the others are occupied, Dewey and Webby Vanderquack head into the Temple of Heroes to find Selene based on the mention of a "Spear of Selene" in Della's letter to Scrooge. However, Webby has become worried that Della's disappearance was because she committed a terrible crime against the family. Dewey, however, is certain that his mother was heroic and whatever she did was for protecting the family. They encounter many obstacles and mythical monsters until they finally reach the entrance to Selene's temple. The doorway opens temporarily, prompting Webby to enter while it is still open. But she is stopped by Dewey, who does not want to find out if his mother was not what he believed, and the two enter a brawl.
Back on the beach, the party quickly turns dull, so Zeus proposed a competition with Scrooge by trapping the ducks inside an electric dome around the island, forcing Scrooge to comply. Huey, Louie, and Donald compete against Storkules, and they are able to win the first round. Furious of the McDucks winning again, Zeus proposes more rounds. Despite Storkules' strength however, he continuously loses against the nephews' ingenuity and resourcefulness. In the final round, Zeus declares the challenge to be getting the Golden Fleece off a little girl named Ligeia. Storkules finds himself caught in a moral dilemma while Donald leaves the games not wanting to be part of the adventure anymore. When Ligeia starts singing, Storkules' mind is taken over by the girl - revealed to be a siren - and Zeus has him attack the boys.
In the temple, Webby comes to understand why Dewey doesn't want to find out if his mother was a traitor and almost decides to leave the temple, but Dewey ultimately changes his mind and takes Webby with him into Selene's temple. Inside, the two are caught off-guard by Selene, who assumed they were Della. To Dewey's dismay, Selene has apparently never heard of the Spear of Selene, as she hasn't seen Della in a long time. However, she does tell Dewey that his mother was devoted to her family, and encourages him not to give up his quest. After receiving the Sphere of Selene from the goddess, Dewey and Webby thank her for helping them.
Back in the competition, Storkules unwillingly tries to crush Huey and Louie with Scrooge powerless to stop Zeus. Overhearing their cries, Donald rushes in and takes on Storkules himself, buying enough time for Louie to convince Ligeia to benefit from her singing and enters a partnership with him. Ligeia gives Louie the fleece, and breaks her control over Storkules. Storkules apologizes for his behavior, but Donald gets over the past and accepts Storkules as his friend, much to Storkules' joy. Scrooge sees how his feud with Zeus has caused their loved ones to suffer and proposes to Zeus to resolve their differences; Zeus, however, still refuses so that he can have at least one victory against Scrooge. Scrooge and Zeus engage in bocce, which Scrooge intentionally loses, and the thunder god wins at last. As the McDucks are prepared to leave, Dewey accidentally drops his sphere as it rolls and knocks out Zeus' ball. Enraged of losing again, Zeus summons a storm, and the McDucks run back to their aeroplane but find Launchpad McQuack has disassembled it during the repair.
- David Tennant as Scrooge McDuck
- Danny Pudi as Huey
- Ben Schwartz as Dewey
- Bobby Moynihan as Louie
- Kate Micucci as Webby Vanderquack
- Tony Anselmo as Donald Duck
- Beck Bennett as Launchpad McQuack
- Michael Chiklis as Zeus
- Nia Vardalos as Selene
- Chris Diamantopoulos as Storkules
- Fred Tatasciore as Charybdis, Ligeia the Siren
- Jenna Lea Rosen as Ligeia (singing voice)
- When Donald says Della can't hear him speaking, a part of his hat disappears.
- Ithaquack was a location in the original DuckTales series as the setting for the episode "Home Sweet Homer".
- The episode's title was first mentioned by Donald in "Woo-oo!". It was also in Della's letter to Scrooge in "The Great Dime Chase!".