It was originally published in Uncle Scrooge Adventures #21, and was later reprinted in a special Gyro Gearloose comic book for Free Comic Book Day 2008.
While out peddling his inventions, Gyro Gearloose is called by Scrooge McDuck to his office. Rats have infested Scrooge's overflow bin, and he demands that Gyro invent something that will rid him and all of Duckburg of the pests. Consulting his "electronic question answerer", Gyro gets the idea to create a cheese with an aroma so irresistible, that all the rats will be attracted to it, and then lead them across the Goose River and blow up the bridge so they can't come back.
The next day, Gyro arrives back at Scrooge's office with his special cheese, and as he walks through Duckburg, all the rats in town follow him. As he gets to the bridge, an officer tells Gyro that he can't blow up the bridge because it's city property. Soon, the rats grow hungrier and begin to eat Gyro and the officer's pants.
Gyro rushes to Scrooge's office to convince him to buy the bridge, only to find out that he went to his money bin. As Gyro runs, rats from neighboring towns join the others in following the scent of the cheese. When he finally reaches Scrooge, they find that billions of rats are swarming up the hill towards the bin, putting Scrooge's money in jeopardy.
As a last resort, Gyro decides to pour the cheese down the drain and into the sewers, hoping that the water will dilute the scent and cause it to lose its strength. But it's still powerful enough for the rats to smell, and they begin to bite through the ground and down toward the plumbing. Eventually, the cheese washes away and the rats begin to depart, leaving the money bin standing on a tall mesa where the hill once was.
- Ludwig Von Drake makes a cameo in this story, poking his head out his laboratory window as Gyro leads the rats out of Duckburg.