- “I wonder if Cluck Kent ever had days like this...”
- ―Fenton after seeing the TV report affirming Launchpad as Gizmoduck
"A Case of Mistaken Secret Identity" is the eighty-fifth episode of DuckTales.
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 Launchpad. 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, Launchpad enjoys the fame of "being" Gizmoduck, until the Beagle Boys capture him. Gizmoduck rescues Launchpad and convinces him that making people believe he's Gizmoduck may be dangerous. However, as the Beagle Boys didn't see Gizmoduck and Launchpad at the same time, they are convinced he somehow freed himself and donned the Gizmosuit. This has the Duckburgians even more convinced that Launchpad is Gizmoduck.
Launchpad 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?
- Hamilton Camp as Fenton Crackshell/Gizmoduck
- Kathleen Freeman as Mrs. Crackshell
- Joan Gerber as Mrs. Beakley, Webwa Walters
- Tress MacNeille as Oprah Webfeet, Hildegard, Woman in Costume, Police Scientist
- Chuck McCann as Burger Beagle, Mover
- Terry McGovern as Launchpad, TV Announcer, Man in Costume
- Russi Taylor as Huey, Dewey, and Louie
- Frank Welker as Bigtime Beagle, Baggy Beagle, Geralduck Rivera
- Alan Young as Scrooge McDuck, Kid in Costume
- Huey, Dewey, and Louie shouldn't think that Launchpad is Gizmoduck because they saw both of them together at the end of "Super DuckTales". They also shouldn’t think Mrs. Beakley is Gizmoduck because they used Gizmoduck to break Scrooge and Mrs. Beakley out of jail in part 4 of that same episode.
- When aired on Toon Disney, the shot of the worker's cigar falling into the crate of fireworks was cut; as a result, the fireworks now seem to ignite entirely on their own, which makes no sense.
- A shot of Big Time hitting Burger on the head was also cut (despite Chip doing the same thing to Dale all the time on Chip 'n Dale Rescue Rangers and not being censored for that reason).
- Launchpad would be mistaken as the secret identity for a superhero again in the Darkwing Duck episode "A Duck By Any Other Name".
- First episode where someone else wears the Gizmoduck armour.