The Killing Jar

Ultra Magnus is taking well-needed relaxing time by gazing at the stars, but also finding they're as troubled as he is, Unicron's giant disembodied noggin probably playing a part in that. A Quintesson ship, containing only a scientist and an Allicon guard, stop by the head to monitor Magnus, the scientist believing that his kind built him too well, and proceeded to engage the mirage system of the ship.
 

Disguised as Sky Lynx, Ultra Magnus is informed that Rodimus Prime needs him to get to the Earth Defense Command central urgently, and the obedient little soldier boards him in no time flat, quickly realising things aren't quite how they should be, the Sky Lynx illusion being dropped and the scientist beginning his test to see how well the city commander deals with betrayal.
 

So Rodimus Prime appears in the room with Magnus and begins dealing fisticuffs to his face, but as the Quintesson predicts, it is only when his life is threatened that he unwillingly attacks his leader, trying to get some sense into the man's head only for superior to vanish, an illusion. The room also drops it's fake appearance, revealing he's inside a cell, so Magnus demonstrates his shoulder missiles and impatience to bust the thing open, failing pretty badly.

The ship then moves onto Chaar, disguising itself as Broadside, oddly, and informing Cyclonus that his grand poobah Galvatron is inside and wants to speak with him. The Quintesson presumes Cyclonus will react much the same as Ultra Magnus, though the Decepticon reacts much quicker to being blasted at by trying to tear his leader's head off, never mind the fact that being socked in the face is everyday treatment for him and the other minions. With Autobots and Decepticons tested, the ship moves onto the next target...
 

Unsuspecting Wreck-Gar! While watching a television show involving a moral-preaching clown, the TV star pops on over to the planet of junk to get Wreck-Gar on the show. The Junkion isn't confused at all by the fact the presumably-highly-paid clown is flying a Junkion ship, but he strolls on inside and finds himself in a completely barren room, the Quintesson predicting he'll just slump into inactivity, what with him as an Autobot. However, distraught by this change, he begins tearing up the walls and floor, much to the Quintesson's surprise, only to make himself a seat to sit on and that's the only comfort he needs. Aw.

Over at the EDC central, Marissa Faireborn demands an incoming ship to identify itself, only to hear that the pilot of it is, in fact, her father! They enjoy a brief embracing, Marissa suggesting she show him around the place, only for the doors of his ship to abruptly close, sealing them in as it removes the disguise and makes a departure. The Quintesson bad mouths the audience while Marissa's father grows a Quintesson head while claiming he's still her father, only to receive a martial art beat down in response. The scientist realises his predictions were correct that humans always resort to violence, and removes another illusion from the cells to allow the inhabitants to see what mess they're in.

This gives them all an opportunity to see if they're all doing fine, to feebly grab the bars and get electrocuted (what would they achieve by grabbing them without being electrocuted?) and shout a bit before the scientist and his guard enter, dubbing them all inferior beings with no use other than to be studied and disposed of. With Marissa giving a lecture about such activity being criminal activity, the Quintesson chooses her to be the first subject, weakening her with a submission device, only for Wreck-Gar to shoot his fist into the device and wreck it, allowing Marissa to give the tentacle freak a mighty shove into his guard.

She uses this opportunity to try and release Ultra Magnus with the Allicon slowly on her trail, only for her hammering on the lock to cause an electro storm that threatens to tear the ship and everyone inside apart! This, somehow, also causes a miniature tornado to sweep the Quintesson into the air for a bit before the Allicon steers the ship out of the storm with relative ease.

With that problem out of the way, Marissa still can't free Ultra Magnus, so he grips the grips and doesn't let go so some wacky visual effects can envelope the screen, short-circuiting the whole thing and removing the bars on all the cells. Even Cyclonus is impressed by this deed, while the Quintesson and Allicon return to complete the examination. The guard duals with Wreck-Gar...
 

Marissa rides on the Quintesson's head. Ultra Magnus and Cyclonus have duties about taking this ship to their respective leaders, and thus start trading blows, while the Allicon starts lopping off Wreck-Gar's arm, though that doesn't exactly mean a lot to our Junkion companion. Marissa begins setting a flight course back home...

Until black hole attack
 

Marissa immediately warns the fighters about their impending doom, while the Quintesson provides a helpful explanation for those who've never heard of a black hole before (in a nutshell, it's the universe's plughole) while the Allicon starts the thrusters to keep them in place while a distress beacon is dispatched. Amidst the confusion, the Quintesson beats an exit...

To the escape pods chamber! The electro storm damaged all of them except for one, and the cowardly slime ball wishes to claim it as his own, but naturally none of the others can accept this and try to get him out, except for the Allicon who can't overwrite his programming and just blanks out when thinking of disobeying his superior.

Ultra Magnus deals with it more bluntly by just plucking the bastard out of the cockpit and throwing him on the ground, though the Quintesson warns him that he has started the launching countdown, meaning Marissa has to get up there in under twenty seconds. Cyclonus, despite being about five times the size of the pod, claims he should have it, though his delaying leaves Marissa only five seconds to make it, and looks like she could make it!

Only for the Allicon to grab her legs while Magnus is lifting her up, pulling her down to the ground while the pod escapes, leaving a gaping hole where it was for Ultra Magnus to be sucked through! Thankfully, Cyclonus uses his tractor beam to pull his foe back into the ship to finish him off personally, though the Quintesson runs in to remind that they're all going to die, though they point the blame on him for capturing them all.

The ship begins flashing psychedelically while the ship receives a message, coming from behind them, apparently, and appears to be a ship belonging to their own alliance from everyone's view, only to realise that it's a derelict ship, their distress signal an automatic one and with no crew to activate thrusters to prevent it from entering the black hole in seconds flat. The Quintesson claims as long as their engines remain functional, they can stay safe for a while longer. "How long is a while longer?" Ultra Magnus asks.

Just shut up in future.

After the inexplicable explosion of their engines, they drift towards the black hole... only to come out the other side, discoloured in crazy fashions. The Quintesson explains that they are in a negative universe, a theory he had that is now proven correct but doesn't really explain what the hell a negative universe is. He then states that if they build up enough speed to re-enter the white hole, they can emerge back in their own universe, so Ultra Magnus and Cyclonus set them to the task.

After the episode's first alliance symbol scene transition, they set about repairing the engine that was damaged by the overload of the thrusters, and they all work together as a team to rebuild it. With the engine repaired after a short montage, the Quintesson claims they'll be welcomed to oblivion if they enter at the wrong trajectory, but they give it a shot anyway.

And unsurprisingly, they end up where they started from, though with daft old Sky Lynx attacking them! The Allicon opens the communicator for Ultra Magnus to tell him what a spoony bard he is and gets him to dock on the ship, allowing the occupants to leave with Ultra Magnus getting Cyclonus to promise he'll do no funny business. He complies, but they agree that the next time they'll meet will be as opponents, not as allies.

With the others returned home, Ultra Magnus and Marissa land upon Cybertron, safe and sound, though Magnus laments that they travelled to another universe and back again, yet the citizens of Cybertron and Chaar are still so far apart. Alas.

Unless Broadside switched sides and everyone was kind enough to keep his little secret, or the Quintessons are just dippy at choosing disguises, Broadside is an Autobot, not a Decepticon.

Marissa Faireborn's father is actually meant to be someone that you may find familiar.

It's Flint from G.I. Joe, aged twenty years or so! Well, apparently. I don't see much of a resemblance beyond the eyebrows, but one of the writers said it so there you go.

The Allicon's mouth plate opens at the top purple part just a large jaw, but sometimes...

It speaks through the bottom of it's mouth. That's weird and slightly gross.

This is the best representation of another universe I've ever seen.