As part of his latest plan, Krang brings General Traag to Earth from Dimension X as a distraction for the Turtles, while Krang tries to turn a laser at the ice and free the Technodrome from its prison at the North Pole. Meanwhile, Donatello learns a new fighting move, Wu Wei, where one ninja turns his opponent's attack against him without action
Michelangelo accidentally turns his brothers into five-year-olds with Donatello's "Food Rebibifier"(a machine that turns old and rotten food fresh again), while Shredder, Rocksteady, and Bebop steal weather balloons and helium tanks.
Slash, the evil mutant turtle, returns to Earth from outer space with a greatly increased IQ and a raygun that turns humans into turtles. He plans to reign as Turtle Supreme, but he will have to get past the Teenage Mutant Ninja Turtles to do it.
Leonardo gets lost following a distress signal while Krang invents a "Hyper-Thruster". Krang tries to blow the Earth off its axis and melt the ice. The Technodrome is not at the bottom of the sea, but is at the North Pole
Michelangelo buys a parrot and names him Ditto, although the bird really belongs to a criminal who is after a rare key around Dido's neck because the Gulubi Ruby, the gem the thief stole, is in a vault that only the key can open.
After winning a free European vacation, the Turtles journey to Paris, France. Meanwhile, Shredder, Rocksteady & Bebop are planning to steal metal from the Eiffel Tower in order to power up the Technodrome.
Still in Paris, the Turtles & Master Splinter visit the Louvre. Meanwhile, due to Shredder's incompetence, Krang's new Hyper Rocket Thruster becomes a Rust Encruster, with which he plans to oxidise the world's famous landmarks & monuments, unless world leaders use their power reserves to bring the Technodrome back to Earth
The Turtles take a tour of Venice, Italy, just in time for the annual Mardi Gras festival, which April is covering for Channel 6. Meanwhile, Shredder & Krang plan to hold the priceless treasures of Venice to ransom by using Krang's HydroFluxor to flood the city.
The Turtles & Splinter arrive in Lisbon, Portugal, just in time for the annual Running of the Bulls. Meanwhile, Shredder & the mutants will use Krang's new heat ray magnifier to burn the city to ashes using the power of the Sun unless the Turtles can stop them.
The TMNT & Splinter journey to Dublin, capital of the Republic of Ireland, land of myth & legend. Meanwhile, Shredder, Rocksteady & Bebop use Krang's Rainbow TransCharmer to transform all of the cute, furry animals in Dublin into vicious beasts.
Shredder takes possession of the mythic sword, Excalibur, and proclaims himself "King Shredder." The Turtles, along with Merlin, must take it from him or else the Medieval Times will merge with the modern world.
The Turtles take a trip on the famous Orient Express that runs from Gare de Lyon in Paris, France to Istanbul, Turkey. But Shredder is also on board and is planning to use Krang's new Super Charger to launch the Orient Express into the world's largest oil
In Amsterdam, Netherlands, the Turtles must stop Shredder from stealing the Duchess Diamond, that Krang needs to power his Laser Dimension Blade. Shredder has some competition though, as two bumbling thieves also want the diamond for themselves.
The Turtles are in England, when they are taken back to the past, via an experimental atomic clock and must team up with Sherlock Holmes and Doctor Watson in order to get the clock back and return to the present.