Scrooge McDuck blames Donald Duck and Fethry Duck of the low sales his newspaper has had lately. Then John D. Rockerduck arribes, angry as he notices McDuck's newspaper is copying the news from his newspaper. Scrooge sends Donald and Fethry after some original news and they return with the news that Rockerduck has bought the pyramid of Keops Jr (not as big as Keops' pyramid, just 3 m high), which will be disassembled and reassembled in Duckburg with a statue of Rockerduck riding a horse on top. However, Rockerduck had already published it, so Scrooge gets angrier at his nephews.
The following day, Scrooge calls Donald and tells him to steal the pyramid before it reaches Duckburg, pretending to be the Duck Avenger (not knowing Donald is the actual Duck Avenger). Scrooge has a hundred thousand newspaper already printed with the tefth news. Donald refuses as the Duck Avenger is his friend and he doesn't want to make the outrageous suspicion befall on him. After Scrooge fails on persuading him, just decides to call someone else.
Donald tries to find who will be the Duck Avenger impersonator and sees Fethry going to the Money Bin, so he awaits Fethry at the exit, and Fethry reveals he will take the pyramid disguised as the Duck Avenger, so Donald invites him to eat at his house and adds "Car-Can Sweeties" to his milk. Fethry takes a nap and Donald, sure that the Duck Avenger's reputation is safe, goes to his room to sleep.
However, a Duck Avenger impersonator still tries to steal the pyramid and fails, but he doesn't mention his failure in time and the newspapers are published with the news of the theft. Donald is awakened by the newsboys yelling the news and believes Fethry woke up, but he is still asleep and the "Car-Can Sweeties" made him forget he had to impersonate the Duck Avenger. Now Donald asks himself who was the fake Avenger.
Donald deduces who was the impersonator, so becomes the Duck Avenger and goes to Scrooge's house. He enters with a jetpack and deactivates a robotic guarddog using an electro-neural lantern, then he reactivates it to attack Scrooge. Scrooge reveald the fake Avenger didn't manage to steal the pyramid but was too late to stop the newsboy, and then the Duck Avenger finds the costume under Scrooge's bed. Scrooge tells that since Donald refused and Fethry didn't appear, he impersonated the Avenger himself, but his failure means his newspaper will lose readers for publishing fake news. The Duck Avenger has a plan to avert it.
The Duck Avenger goes to Rockerduck's house and pretends to have an accident. Rockerduck tries to tie his hands but the Avenger reveals he was wearing fake hands. Rockerduck follows the Duck Avenger and screams to some nearby cops to help catch him. The cops don't manage to see them but follow the voice. They reach Donald's toolshed where the Avenger uses a sleeping spray on Rockerduck and dresses him in his costume, then he becomes Donald and uses his secret elevator to return to his room.
The cops arrive, knock Donald's door and he opens pretending having just awakened. They all go to the toolshed where they find "the Duck Avenger" who is unmasked as Rockerduck, so he either is the actual Avenger or is crazy and will go to an insane asylum. Donald tells Rockerduck that the only option to save himself is to tell he's a sonambule and that he will donate ten thousand dollars to the police box. Besides, he will have to tell that while the Duck Avenger didn't steal Keops Jr's pyramid, he bought it to Rockerduck to donate it to the city.
Two days later, the pyramid is revealed with a statue of the Duck Avenger instead of Rockerduck, but Rockerduck still publishes the news first and Scrooge is angry again with Donald and Fethry.
- One of the first things Donald says to refuse the impersonation is that the Duck Avenger doesn't steal, but he did so in his first few appearances.