"Fishy Business" is part one of the tenth episode in the third season of Courage the Cowardly Dog, written by Bruce Wilpon and David Steven Cohen, which aired July 19, 2002, preceding "Angry Nasty People." It is the thirty-sixth airing and seventy-first episode overall.
At the Farmhouse, Courage is attempting to teach his pet fish to jump through a hoop while Muriel is serving seafood to everyone. Courage notices a fish-like woman outside the window and becomes frightened. Shortly after, there's a knock on the door, and the same fish Courage saw shows up at the door. She tells the residents that she is a Fishionary and that she is there to take them all "back from once they came". She has a bus outside waiting for them and they all board while Courage is trying to prevent them from going.
As they are riding on the bus, Courage notices that the bus is descending into water and they all end up in an Underwater Courtroom run by three fish Judges and an Octopus as their bailiff. Courage and his owners are in a trial-like setting and are found guilty of participating in uncivilized (human) activities such as watching television, having a pet fish, and eating seafood. They are then sentenced to "the bowl", a giant fish bowl used to convert humans into fish by donning them with artificial gills and feeding them fish food until they are fully converted into fish. When the transformation is complete, they will be released into the open waters (using Di Lung as an example).
Muriel, Eustace and Courage are forced into the gills and tossed into the fish bowl. After being fed fish food and seeing his reflection in a decorative treasure chest, Courage realizes that he has to figure out a way to escape their underwater prison. He takes off his gills and jumps onto the giant fish food container the octopus is holding and gets flung back into the courtroom. He manages to connect the octopus's tentacles to the bus and to the fish bowl and drives the bus, with the octopus and fish bowl in tow, towards the surface and to the farmhouse.
The three fish Judges are shown getting a massage from lobsters. They catch Courage escaping with Eustace and Muriel, and use the lobsters to chase after him. Courage makes it to the farmhouse with Muriel and Eustace still in the bowl. As he enters the farmhouse, he and the judges find the Fishionary watching TV while being fanned by human males. The three fish Judges are infuriated by the sight of their Fishionary engaging in human activities and they sentence her to the bowl.
At the farmhouse, Muriel is soaking in a bathtub that was brought into the living room and Eustace is being fed fish food, showing that they have not fully gotten over the effects of being treated like fish.
- King Ghidorah (Seen on Bagge's Television)