In an attempt to stop evil Coop from destroying their dimension, Coop and Gorrath, assisted by alternate Jamie, launch a desperate assault on the evil Coop.
In the last days of the Earth War, Jamie and Kiva were busy shutting down the Glorft Core Destroyer, while Coop and the Glorft, led by Gorrath as usual, were fighting out. However, Coop and Gorrath get transported to a mirror dimension - because of a gamepad combo that activated the Transdimension Device - where Coop meets his alternate self, a futuristic, evil, and muscular warlord version of himself at that, having defeated the Glorft, abandoned Megas, formed an Empire, and keeps on destroying - no matter the location, time, dimension and enemy. He also sees that Kiva has turned cyborg as well and is evil Coop's sidekick. Alternate Jamie, on the other hand, has lost his cowardice forever and became strong enough to try and defeat evil Coop and his empire with his Resistance (and on a side note, Jamie and Kiva were dating in the future). Coop and Gorrath must work together this time to stop mirror Coop and prevent him from ever destroying Earth again.
Coop's builds the world's most powerful universal remote - and Skalgar (who Coop and Jamie called "School Girl"), an ignorant, alien criminal with an inferiority complex, wants it, believing its (non-existent) destructive power can boost his reputation. Coop underestimates his short opponent, and Skalgar teleports the remote to his own mech. Coop then typically destroys half of Jersey City attempting to recover the remote.
Coop, Jamie and Kiva teleport themselves to a planet with brainwashed robots who act like sissies and workers. The alien who did it tries to do the same to Megas, but his brainwasher device only works on sentient robots. (Obviously, Coop's doesn't count.) Coop tries to put the alien out of business for good without unnecessarily destroying the prisoners. Coop in the end destroys the mind control device, freeing the robots. He then leaves the planet, unfortunatly as the group leaves it's shown that the planet was actually a prison to the worst robots in the universe. Who start destroying the planet after they leave.
Coop crashlands on an icy planet and ends up destroying its only mechanized guardian. Now he must protect the Yetis there from selfish, ice-hungry robots named the Cerilians, who use it to maintain their cooling systems. Trouble is, Megas is iced over, and does some of the Cerilian Army's work for him. This is going to be one icy battle for the team.
The Glorft, disguised as a motorcycle gang thanks to their latest Holo-Camouflages, comes to a rock concert. They're not there for entertainment, however - they want to eliminate Kiva's ancestor, which in turn would cause Kiva to cease to exist, which in turn would mean Megas would stay with the Glorft and never reach Coop, which would in turn doom Earth into extinction. Kiva and Jamie must protect the ancestor until Coop can get to Megas. To make matters worse, it seems that Jamie and has fallen for Kiva's ancestor and she has fallen for him.
Once again, Coop mistakenly releases a giant, plant-type alien menace that wants to destroy Earth and acquire its heat. Fortunately, Megas is too big for the plant to handle, so it has to find a bigger form. Unfortunately, this is Thanksgiving, and the spore fuses with a bunch of parade balloons to this end. Coop now must prevent the plant from wrecking the holiday.
Kiva gets some unwanted attention from Captain Warlock, a space pirate who goes for red heads, and now must make a choice between a possible time drive or two complete idiots. As usual, one wrong choice means certain death. Now Kiva must find a way to free Coop and Jamie as well as fend of the advances of one love sick space pirate and his mechanized crew.
The S-Force has been captured by an evil villain named Zarek, and he is planning to execute them. Fortunately, Jax escapes and manages to enlist Coop's help. Coop manages to save the S-Force from the "infinity zone," which Coop, Jamie, Kiva, the S-Force, and Megas fall into, but survive the Infinity Zone after Coop helps everyone escape, but now Zarek is sending down an entire army to terminate them. It's Megas and the Ultra-Dimensional Power Zorp vs. a bunch of insect robots! The "gift" that Zarek offers Coop, Jamie and Kiva is an end to their lives, whereas the "gifts" Coop tries to give Zarek, but almost destroys the S-Force with, is actually thousands of missiles being fired at Zarek, due to the new Super Destructor Mode.
Coop, Jamie and Kiva head off to Las Vegas, and inadvertently discover Area 50. Coop accidentally activates a destructive energy-leech robot, who, due to severe and fatal programming errors, sees everything as "the enemy." Coop further screws up by directing the robot to Las Vegas. Now Coop must find a way to shut down the robot permanently before Las Vegas loses all its power. Coop in the end destroying the cities power source causing the robot to deactivate. And he then buried the robot in the Grand Canyon which he had to fill with dirt.
Coop inadvertently frees the Glorft from no-space, allowing Gorrath to start his revenge. The only thing Coop is worried about, however, is babysitting cousin Skippy, who is easily bored and hates everything about Coop's house. In an effort to get him to shut up, Coop takes Skippy to the moon in Megas. (Incredibly, he is still bored.) There he discovers the Glorft is plotting to smash the moon into the Earth. Coop has to fight off the Glorft while making sure Skippy doesn't end up Glorft fodder.
It's 5:01 and a video is due back at the rental store by 5:30, and Coop has to get it there on time to keep his membership from being revoked. However, Magnanimous appears and challenges Coop to protect his title against several robots, including one resembling Mr. T. Coop manages to beat the robots, but inadvertently challenges the entire galaxy to fight him - and the galaxy takes him up on the offer.
In an effort to impress some Sailor Senshi-style space girls, known as the Ultra-Cadets, Jamie poses as Coop and is taken to their planet, where he learns the Ultra Cadets' city is in trouble from a giant fire monster. Armed only with an age-old, feminine robot, Jamie "fights" the monster and defeats it the way Coop always does: sheer luck. However, Coop arrives with Megas to save Jamie and gets into a fight with the mechanized Ultra Cadets.
