Thanks to a malfunction in Donatello's Inter-Dimensional Early Warning Detection Machine, a tear has occurred in the fabric of space and time, allowing two heinous criminals from Dimension X, Skaarg and Dementor, to arrive in the city.

Splinter is contacted telepathically by his sensei, Master Mogo-san who requests that Splinter meet him at Pier 17.

The turtles, Groundchuck and Dirtbag are taken to Shellri-La by an alien "Turtleoid" named Kerma. Kerma seeks help from the turtles to defend his planet from a two-headed dragon named Herman the Horrible.

The turtles unmask the dragon as they prove that the menacing creature is actually operated by two renegade Turtleoid delegates. Kerma return the turtles back to Earth, where they destroy Shredder's new Technodrome Mark II and afterwards defeat Chrome Dome.

While rummaging through the local junkyard the Turtles witness the crash landing of an alien spacecraft.

At the Museum of Fine Art Shredder uses his time portal to journey back to ancient Japan so that he can destroy Splinter and the turtles.

Krang, Shredder, Bebop and Rocksteady break in to the City Hall Records Department and steal maps of the sewer system dated 1895.

While investigating the most recent robbery perpetrated by the Mole Squad, April and the Turtles stumble upon a secret meeting between the Mole Squad and Dr. Floyd O'Toole, a scientist who has been missing for weeks.

The Turtles visit April at Channel Six News and ask her if they could use the stations' equipment to contact their old Turtleoid buddy, Kerma, on Shell-Ri-La.

Thanks to Vernon's irresponsible journalism, the Turtles find it necessary to stand guard at the Genetic Research Lab.

While surfing in the white water rapids of the sewer, Michaelangelo is rescued by Merdude. Tthe Turtles, using Donatello's Porta-Tracker, volunteer to help Merdude find his way back home.

After an unsuccessful attempt at capturing Razar and Toka, the Turtles return to the lair to see the eccentric billionaire, A. J. Howard, spouting his ideology and his hatred for mutants across the airwaves.

Krang makes copies of himself and sets them loose to attack the turtles.

There is a new amusement park in town and called Combat Land. The park's owner, Horatio Stressbar, has been unable to find anyone with the combat skills to give his robotic warriors a thorough work out.

Shredder, Rocksteady, and Bebop arrive at the Asian arts exhibit and proceed to loot. The turtles head out to stop them despite a grave warning from Splinter that there will be dire consequences.

On their latest trip to Earth, Bebop and Rocksteady steal a machine that makes everyone scared of everything.

Splinter suffers amnesia as the Turtles try to remind him that he is the true leader of the Foot Clan.

Irma is kidnapped by Bebop and Rocksteady and is replaced by a robot that looks just like her that is programmed to eliminate the turtles.

Zach and his brother Walt visit the Turtles. As they leave, Walt takes a map that could guide Shredder to the lair if it happens to fall into the wrong hands.

Shredder tries to trick the Turtles into eating cookies made with anti-mutagen. Michaelangelo, wanting to be a human, tries one of the cookies and it mutates him into a teenager.

A series of baffling crimes are being committed by "brawny burglars" with thick Austrian accents and the Turtles are on the case, but so is Casey Jones and that could mean nothing but trouble for the Turtles.

Krang's attempt to split the Inter-Dimensional portal goes awry. By utilizing the pirate radio station WOOF Krang believes that he can use the station to lure the City's populace into Krang's Chasm.

Irma accidentally becomes gigantic and her naturally clumsy nature makes her a danger to the city.

The Turtles must clear their names when they are believed to be jewel thieves who stole a priceless emerald during a magic act run by a wizard named Boldini.

Krang hires a multi-dimentional ring-master who intends on making the Teenage Mutant Ninja Turtles part of his circus by using an anti-aging serum.