Up in the mountains, Uncle Otis is prospecting for gold but is having trouble finding any due to the snow. Luckily, for Otis, a beaver slapping his tail is able to loosen the snow, and thereby allow Otis to soon locate a huge gold nugget that he loads on his minecart to take back to Adventure Bay to show his niece, Mayor Goodway. However, he barely starts off before the old, rusted rails cause the mine cart to derail and go racing off down the mountainside, drawing attention from Jake and Everest, who contact Ryder to warn him of Otis' situation.
At the Lookout, the pups are looking for their very first squeaky chew toy, and soon find it, before Ryder gets Jake and Everest's call for help saving Otis. Ryder summons the pups to the Lookout, and once they are assembled, Ryder has Rubble join him to go rescue Otis while having Everest aid them from her location with Jake. The team heads out to help Otis.
While Rubble sets up a barricade to protect Otis' cabin from his runaway mine cart, Everest and Ryder rescue Otis, but soon find themselves having to deal with the nugget trying to run them over after it falls out of the mine cart. After some effort, Otis and Everest avoid being run over, but they soon see the nugget heading for the lodge of a beaver family nearby. Ryder summons Marshall to assist with protecting the beavers, and manage to stop the nugget safely. With the nugget secured and Otis safe, along with his cabin and the beaver family, they head back to Adventure Bay with Rubble towing the nugget in the mine cart with his digger.
Once back in town, Mayor Goodway reprimands her uncle for his actions and suggests he give up prospecting, but Otis reveals why he found the nugget to begin with as he chips off a piece to place as the centerpiece of a necklace he gives to his niece, which she is grateful for, before then explaining that he plans to donate the rest of the nugget to help mend the rusted rails that caused all this trouble to begin with, which everyone fully supports.