In J&D's ToonWorld, Madame Mousey is a member of The E.V.I.L Troop.
She faked being a soothsayer to get money from the mice. She created the Manhattan monster to get rid of the rodents because when she ran away from her owner, the other dogs didn't want to be around a dog who looks similar to a rodent. She snapped and got cats to help her make a monster to wipe away all the rodents of New York. She locked them in crates and sold them to cats to be eaten. In the end, Fievel knocks her out by using a live wire to shock her. At the end of the fight with the cats, Tiger and Tony catch Mousey from escaping into the sewer, and the dog council sends her back to her owner. She claimed it was even worse than going to the city pound.
She despises Nellie for doubting the beliefs of the night monster and underestimating her. She gave Tony a fake clue to the night monster so Fievel and Nellie could go to an old house to be finished off.
- She normally speaks with a French accent, but switches to a Brooklyn accent when angry, hinting that the French one is false.
- Mousey was considered to be a better villain than the villains in the third American Tail film.
- As revealed in ToonWorld All-Stars: The Movie, Madame Mousey is mostly seen with Jelly Otter (evil version) and Dark R1 Rayman/Raymesis Jr.