"The Return of Dregg" is the first episode of the tenth and last season of 1987 Teenage Mutant Ninja Turtles cartoon series.
The episode starts at the lair, with the pieces of the Vortex Crystal they've found in the previous episode "Doomquest", the Turtles' uses them to cure them from their out-of-control mutations.Michelangelo is wired to de-mutation ray to be cured. Once they go through the rays they have to make sure the genes are normal. Suddenly, Michelangelo didn't feel right, he began to mutate, larger then before. Now he able to fire energy beams from the wrist. The other Turtles and Carter tempt to hold him off with no success. Michelangelo breaks Donatello's bo. Carter lassos a chain, Michelangelo gets free with torch breath. Then he breaks Leonardo's and Raphael's weapons with his extended claws. It turns worse when Michelangelo mutates even further, so large that he cause the lair to cave-in. It all turns out to be a virtual reality simulation what would of happen if use the ray on themselves. Splinter advises that stormy seas grow calm when the wind stops blowing, calm the mind and you'll find the answer. Donatello will run on another test. Meanwhile on a far-out planet. Batmen are repairing the Dreggnought, while Lord Dregg and HiTech are observing the sensors for Vortex Crystal, which its found on Earth. Dregg states the Turtles had discovered that the crystal has the power to stabilized their mutations, but due to low readings, they have a few fragments. With a tiny piece Dregg can genetically recreate another crystal then complete his Vortex Transporter. His other assistant Mung reports that the Dreggnought is ready for departure. HiTech tells Dregg even they return to Earth it will take months to construct the transporter, then Mung shows a container filled with over a million computerized Microbots, they can build whatever Dregg desire in only hours. Dregg then offers Mung to leave the current planet to his second-in-command, HiTech protests the offer, stating the he is second-in-command, no one but Dregg is superior to HiTech. He fired hid laser at Mung who puts up shield, then signals the Batmen with his antennas to shoot web fluid at HiTech, restraining him to a chair. As the pod closes, Dregg will be sending HiTech on a mission, orbit the galaxy like a space probe and return with untold data in 2,000 lightyears. Dregg launches HiTechs away while he and Mung departs to Earth. Back at the lair, Carter adjusted the ray to match the Turtles genetic codes, with a another test it's successful, but it doesn't work on Carter, Splinter encourages Carter to find a cure. The Dreggnought arrives near Earth, using the scanners, the Vortex Crystal has been in New York City where the Turtles are. Dregg trusts Mung's Microbots can accomplish the task and is amused with the idea of using a micro rocket. Mung send one Microbot to Earth to get a piece of the crystal. Due to rockets small size it was undetectable. At the lair, Raphael, Donatello, Michelangelo, and Leonardo are wired for the de-mutation ray while Splinter and Carter get the controls ready. The Microbot made its way to lair and gotten piece of the crystal while Leonardo was being stabilized. They normally mutate when their over stressed, they spar to make sure their cured. In a while, Carter decided to return to college to continue his studies in bio chemistry to find a cure for his mutation. Leonardo shakes hands, but noticed his hand is glowing and mutates larger then before.
Raphael complains that Leonardo berated him for missing with vr simulator now he's doing it, but got lifted and tossed, Donatello assured that Leonardo really mutated. The mutated Leonardo began trashing the lair, he escapes when the other turtles tried to hold him off. They went after him in the Turtle Van, while Carter stayed behind to find out what cause a power drop during the stabilization for Leonardo. The micro rocket returns to the Dreggnought with the Microbot and a fragment of the Vortex Crystal. Dregg regrows the crystals and will use it to power his teleporter that send anything to one end of the galaxy to the other, as well to destroy the Turtles. Mung sends the container of Microbots to Earth to build the transporter. Back at the city, Leonardo rampages the streets, the other turtles halt the van in front of him, attempting to calm him down, but took a lamppost and strikes the van. With a news crew watching the events, the turtles must capture Leonardo before they have more problems. Donatello toss his bo in the air, Leonardo catches it, Raphael thrown his sais at the wrist to hold to the bands, Michelangelo uses the turtle line hold his ankle, but Leonardo brakes free, dragging Michelangelo with him, and cause the gas station to explode. Donatello orders Raphael to call April to see if she can take them off the 11:00 news. At April's place, Raphael called her and filled in of what is going on, the news is already airing. The line breaks off of Leonardo ankle, he climbs on a bridge and catches a ride on a train that's heading downtown, so the Turtles pursued in the van. At the Dreggnought, Mung shows Dregg the news and sees that one of the turtles mutanted, this well make his plan to conquer Earth a lot easier, he orders Mung to prepare the shuttle. Back to Earth, the Microbot container lands near a plant, after it destroys a security guards gun and fled, they freely consumes every equipment they get on and assembles a base and the Vortex Transporter. Meanwhile, the other turtles find Leonardo resting on a sandbox in a park. Before they catch him, a shuttle arrives reveals to be Dregg and his new soilders, who then open fire.
The Batmen fires their laser rifles at the turtles, this awaken Leonardo and attacks the shuttle, only for Dregg orders Mung to flee. Michelangelo came up to thank Leonardo for the save only to knocked over, they chase resumes. At a diner, Carter looks at the result and discovers that someone or something stole a piece of the crystal. A waitress who is serving him sees the mutated Leonardo heading straight for the diner, everyone ran. Leonardo attacks Carter, which trigger his mutant form and fights him. The turtles arrived just in time as Carter knocks Leonardo the ground allowing the others to tie him, Carter then reverts to normal. He tells the others that found the error, he can explain on their way back to the lair. At April's apartment, she working on a article tell power went out, it happened at the hydro-electric dam where she went to investigate. When she arrived, she sees the engineers trapped in a glass tube while the Microbots consume a generator. April then follows cords to the plant where the Microbots build the transporter and also finds Dregg there as well. She called the Turtles to warn them, but got caught by a Batmen, they made their way right now. The Batmen brought April to Dregg who decides to make her the first subject for the transporter. When April about to be sent to other end of the galaxy, the Turtles and Carter arrived just in time. The Batmen fired, they dodged, two of them jumped Carter, but mutates and tossed them to a wall, Raphael caught by the wrist with his sais. Michelangelo throws his turtle line to Donatello who bats it to round up the Batmen. Mung uses the Microbots to construct a giant robot with a blaster to capture the mutants. Carter jumps on the back, but thrown off. Michelangelo uses the turtle line to distract the robot while Donatello torches the joint to make fall, but the robot fired, causing the mutants to land in front of Mung and the Batmen, Carter changes to normal, Mung used to Microbots to make braces on the turtles and Carter, they then placed on the transporter with April to be sent at the center of the sun. Suddenly, Leonardo recovers and knocked Dregg, the Batmen fired, but their lasers doesn't affect the mutanted turtle, Leonardo tossed the robot out of the plant and freed the others. Before Leonardo gets Dregg, he fired a laser which stunned him, a Microbot gets a piece of the spiked shell. Dregg and his forces escapes in the transporter, while Carter overloads it to make sure he doesn't return. Everyone escaped the plant before it explodes. At the Dreggnought, Mung apologies for the failure, but Dregg had all planed out. The mutated turtle shell piece he obtained well help him gain unimaginable power. He also kept a fragment of the Vortex Crystal and one Microbot, with one they can multiply into billions, then another Vortex Transporter will be built, and Earth will be Dregg's. At the lair, Leonardo is kept in a wooden cage, Carter decides to remain with the Turtles and find a cure. Raphael agrees cause they need a lot of help taming the mutated Leonardo, he then puts up a sign says "Do not feed the mutant".
- Leonardo (Cam Clarke)
- Donatello (Barry Gordon)
- Raphael (Michael Gough)
- Michelangelo (Townsend Coleman)
- Splinter (Peter Renaday)
- Carter (Bumper Robinson)
- April O'Neil (Renae Jacobs)
- Lord Dregg (Tony Jay)
- Mung (Cam Clarke)
- HiTech (Michael Gough)
- Turtle Van
- Carter's motorcycle
- April's car
Home media releases
- Teenage Mutant Ninja Turtles Volume 1
- Teenage Mutant Ninja Turtles: The Complete Final Season
- Teenage Mutant Ninja Turtles: The Complete Classic Series Collection
- Dregg uses the phrase "2,000 lightyears" to mean a space of time, but lightyears are used to measure distance, not time.
- When Carter announces that he is stabilizing Leonardo, his mouth doesn't move.
- As the Turtles find mutated Leonardo outside the cinema, the lettering on the front of the Turtle Van is black instead of white.
- When mutated Leonardo attacks the Turtle Van with a street light, the lettering on the front of the Turtle Van is black again.
- Dregg's microbots approach the side of the security guard's desk twice.
- When Donatello tells Michelangelo and Raphael to tie up mutated Leonardo at the diner, Donatello's voice is heard but Raphael's mouth is moving.
- Right after the turtles break through the wall in the Turtle Van to rescue April, lettering on the front of the Turtle Van is black once again.
- When the Turtles flee Dregg's hideout as it explodes, the lettering on the front of the Turtle Van is - you guessed it - black instead of white.