Shredder, Rocksteady and Bebop attempt to break into Tropotron Labs in search of an mutagenic compound, X-7, which Krang thinks could demutate the Turtles. Unknown to them, the two garbagemen Garson Grunge and Joe Junkee are working just below the laboratory's windows.
The Turtles are watching a monster movie when April alerts them to the break-in. As they make their way there, Rocksteady and Bebop decide to trash the lab, pouring a barrel of green liquid out onto Garson and Joe. When the Turtles arrive, Shredder thwarts them with a smoke bomb, leaving them to make a humiliated defeat in front of news cameras.
Garson and Joe find that they have been transformed into garbage mutants. As they roam the streets, they see a news broadcast of the Turtles fleeing the lab, and come to the conclusion that the Turtles are responsible for their current plight. Vowing revenge, they rename themselves Muckman and Joe Eyeball.
Krang sees April's coverage of the strange new mutants, which are linked to the two "missing" garbagemen. He and Shredder conclude that they might be useful in getting rid of the Turtles.
April and Irma go out in search of the garbagemen, and are quickly cornered by Muckman and Joe Eyeball. The Turtles manage to get to the alley quickly, but as they approach Muckman and Joe, the two new mutants begin glowing. The Turtles suddenly grow weak and collapse, and are unable to keep their friends from being abducted.
Still weakened, they flee back to the lair, where Splinter brings them soup. The Turtles are desperate to save April and Irma, but are barely even able to sit up.
Shredder surfaces in the city with a mutagen tracker, which leads him to the abandoned warehouse where Muckman and Joe Eyeball are keeping April and Irma captive. Shredder pretends that the Turtles were the ones who mutated Rocksteady and Bebop, which immediately wins the sympathy of Muckman and Joe.
After figuring out that proximity to Muckman weakened them, Donatello heads back to the lab to find a sample of the mutagen in order to make an antidote. Leonardo, Raphael and Michelangelo try to track down April and Irma, but only end up surprising Donatello instead. They then discover that they have walked into a trap by Shredder and his new allies, and the proximity of Muckman causes them to be overcome with weakness again. Splinter attempts to intervene, but when Shredder threatens the Turtles' lives, he is captured as well.
As Shredder drags his old enemy off to the Technodrome, Muckman and Joe Eyeball prepare to kill the Turtles. However, April manages to convince the pair to let her prove the Turtles' innocence, and shows them security camera footage of Rocksteady and Bebop dumping the mutagen. Realizing their mistake, they assist a weakened Donatello in formulating an antidote for the Turtles.
As soon as they have regained their strength, the Turtles use the portable portal to transport themselves to the Technodrome, along with Muckman and Joe Eyeball. After a battle against Rocksteady, Bebop and the Foot Soldiers, they manage to rescue Splinter from being dropped into a vat of mutagen, and leap back through the portal just before it closes.
That evening, the Turtles have a small party with April, Irma, Muckman and Joe Eyeball. Donatello says that he might be able to reverse the pair's mutations, but Muckman tells him to take his time, since they are now mutant heroes rather than ordinary garbagemen. Much to the Turtles' disgust, the pair then begin eating rotten food out of the fridge.
- Leonardo (Cam Clarke)
- Donatello (Barry Gordon)
- Michelangelo (Townsend Coleman)
- Raphael (Rob Paulsen)
- Hamato Yoshi/Splinter (Peter Renaday)
- April O'Neil (Renae Jacobs)
- Irma Langinstein (Jennifer Darling)
- Shredder (James Avery)
- Krang (Pat Fraley)
- Rocksteady (Cam Clarke)
- Bebop (Barry Gordon)
- Garson Grunge/Muckman (Townsend Coleman)
- Joe Junkee/Joe Eyeball (Rob Paulsen)
- Tropotron Labs security guard (Peter Renaday)
- News anchor (Cam Clarke)
Home media releases
- Teenage Mutant Ninja Turtles Season 5
- Teenage Mutant Ninja Turtles: The Complete Classic Series Collection
- A small flap which looks to be the Transport Module's door and it's seat appear on the side of the Module nearest the drill when Shredder and the mutants flee the lab after the Turtles intercept them.
- The Mutagen vat is seen as full after Splinter tipped out it's contents out on Krang and Shredder earlier.
- When Muckman said that the Turtles are a real menace, he spoke with Joe Eyeball's voice.
- When Shredder and the mutants arrived back at the city to locate Muckman and Joe Eyeball, the module door opened downwards instead of up and was missing it's window.
- Krang's corneas are coloured dark purple for this episode and "Landlord of the Flies".
- Shredder's piece of dialogue is spoken by Jim Cummings when he and the mutants head back to the Module.