Huey, Dewey, and Louie suspect Launchpad McQuack to be Gizmoduck, which offends Fenton. During a party in honor to Gizmoduck, most attendants dress as him, so the real one cannot prove his identity to show he isn't Launchpad. An accident happens with the fireworks and Gizmoduck takes them away, except for one that hits McQuack. Seeing him as damaged as Gizmoduck should be by taking the fireworks away, everybody in Duckburg is convinced he is Gizmoduck (save for, of course, those who already know Fenton's secret).
During the following days, McQuack enjoys the fame of "being" Gizmoduck, until the Beagle Boys capture him. Gizmoduck rescues McQuack and convinces him that making people believe he's Gizmoduck may be dangerous. However, as the Beagle Boys didn't see Gizmoduck and McQuack at the same time, they are convinced he somehow freed himself and donned the Gizmosuit. This has the Duckburgians even more convinced that McQuack is Gizmoduck.
McQuack decides to confess on national TV that he isn't Gizmoduck, but when he says the idea is "as my friend Fenton says, Blabberin' blatherskite". As M'Ma Crackshell is watching the declaration on TV, the TV speaker transmits the password to the Gizmosuit which goes where Launchpad is and turns him into Gizmoduck. However, as he is unaccustomed to the Gizmosuit, Launchpad makes some mistakes that end up causing a flood, so he must be saved by an unarmored Fenton.
Days later, Huey, Dewey, and Louie have noticed that, after Launchpad's clumsiness with the suit, he cannot be Gizmoduck. Fenton is happy to know he's suspect number 2, after... Mrs. Beakley?
- Huey, Dewey, and Louie shouldn't think that Launchpad is Gizmoduck because they saw both of them together at the end of "Super DuckTales".
- Launchpad would be mistaken as the secret identity for a superhero again in the Darkwing Duck episode "A Duck By Any Other Name".