Donald is angry to find there's a rock star pretending to be the Duck Avenger, and takes Huey, Dewey and Louie to one of his concerts to find out more. He finds that Scrooge McDuck is the sponsor of this Duck Avenger superstar, and the superstar tells the audience to not lose his intergalacting meeting in a month. While Donald argues Scrooge is staining the Duck Avenger's name, Dewey suggests to his brothers to sneak into the Duck Avenger superstar's dressing room to find who he is, but they only manage to see a disguised spy being kicked out. The spy takes a cab to the Rockerduck building.
onald thinks martians wouldn't come just to see a concert, and goes to see the only person he knows who can invent galactic tricks: Gyro Gearloose. Gyro doesn't know anything about the martians, but gives Donald a flying saucer he invented.
That night, the Duck Avenger stealthily follows Scrooge with his flying saucer to an old factory, where Scrooge reunites with Gladstone Gander (who is the Duck Avenger singer), actors dressed as martians, a famous film director and his technicians. The Avenger thinks he will need something more grandiose than his usual methods, so he goes to see John D. Rockerduck and offers him an alliance.
The following days, tourists come from everywhere awaiting the concert, and Scrooge prepares the place for the "intergalactic meeting". Donald also has Gyro preparing some gadgets.
That night, Scrooge is visited by the Duck Avenger accompanied by flying saucers. The Avenger tells Scrooge that he acts to solve trouble and help the weak, not for making Scrooge earn noney, so he will have to return the money for the concert, which must still be played to the Duckburgians' enjoyment. The Duck Avenger then returns with Gyro, as it turns the saucers were his inventions, financed by Rockerduck. Donald returns home two hours later and tells the kids he was with the Duck Avenger and the martians.
The following day, Donald and the kids see Gladstone sad for having to work and not getting earnings, Scrooge returning the money to the audience, and even Rockerduck is upset, as he spent a lot of money to humiliate Scrooge and cannot get the satisfaction of telling it.