The Turtles are going on the offensive in the war against the Krang. This time we have help in the form of a motley crew of mutants that call themselves The Mighty Mutanimals. They consist of Leatherhead, the simian super brain Dr. Rockwell, Slash, the Peter the Pigeon. Their mentor or leader is Mr. Kurtzman, the conspiracy enthusiast who helped the Turtles in the past. There is excitement is the there as Donnie discovered a way to cure the humans of the mutagen and return them safely to earth. 
This hour long episode gives the Turtles and Mutanimals a chance to strike a crippling blow to the Krang and hopefully get rid of them forever.
The first half of the episode, Donnie finds out that Mikey just unlocked the formula to super charge the retro-mutagen process from months to a matter of hours for them to have enough to cure the entire city. Unfortunately, Mikey couldn’t remember how he did it…typical. Splinter orders the Turtles to find the humans and rescue them. April tells them that her psychic ability knows that they are being held in Dimension X as worker slaves. While searching for the remaining humans in the city, the Turtles stumble upon old friends and adversaries. It turns out that Kurtzman has recruited them to fight the Krang, when the Turtles left the city. The reunion is bittersweet, but their mission takes priority. Kurtzman discovers that the Krang has enough mutagen to infect the whole world and the Turtles and the Mutanimals must stop them from turning earth into another Dimension X. They find the delivery system for the mutagen. It is a large rocket filled with it. A familiar Krang watches over the rocket, Krang Sub-prime. Gilbert Gottfried voices the Krang Sub leader. Working as a team, the Turtles and the Mutanimals are able stop the Krang from their evil plan. The battle scenes are great, and watching the Turtles and their new allies work together is very entertaining.
The second half of the episode focuses on getting the humans back from Dimension X and returning them back to normal. Team Mutanimals strike a blow at the TCRI building where the portal machine is located. They activate the portal to Dimension X, while Team Turtle use their new invention, the Turtle Blimp to fly up into the portal and enter Dimension X. One thing I have to say..Savage Mike is back and I love it. 
His wacky, spacey, way of thinking in Dimension X becomes a major advantage to saving the humans, not to mention saving his brother’s bacon from alien eating slugs, and monsters. But somehow Krang Sub-prime sneaked his way back to Dimension X and is trying to stop them from saving the humans. The fight scenes are great, but I love the flying chase scene with Mikey in the pilot seat maneuvering a Krang Technodrome through Dimension X with a Krang robotic monster on his tail. The Turtles are able to find the humans, return them back to normal, and with the help of the Mutanimals keeping the portal open, transport everybody safely back home. The Krang Sub-prime fails to stop them and crashes his ship into an asteroid. His last words were….OH KRANG!!!!. I believe that is an expression that means “OH S*&T!!! in Krang. It’s kind of catchy.
If you ask me, Mikey should be applauded for his heroic efforts in this whole ordeal. First he accidentally discovers a new batch retro mutagen, then he uses his Dimension X survival and fighting ability to save his brothers, and he also is able to help Donnie convert the mutagen into the retro mutagen on the Technodrome for the humans. The Turtles and the Mutanimals save New York. Next stop…Shredder, and saving Karai.
