Starscream, Thundercracker and Skywarp are being chased by the Aerialbots. Silverbolt says they've got to stop the Decepticons, but Slingshot isn't too happy they're going through all this for some stupid humans. And Skydive says that from what he's learnt about this planet, they wouldn't be missed! Skywarp then attacks Slingshot from above...

...but Skydive blasts him. Slingshot and Fireflight then shoot at Thundercracker, but he dodges their shots by spinning around, impressing Slingshot.

Air Raid then dives in and collides with Thundercracker, forcing the latter to transform. As Skywarp says these punks are all over them, Starscream says there is only one way to get the Aerialbots off their tails, and that's to...

...dump the chumps! He releases a bunch of humans he'd taken hostage, and as he and the other Decepticons fly away, the Aerialbots quickly save everyone. They return to the Autobot HQ, some of the Aerialbots talk about how incredible the Decepticons are.

Ratchet tells Slingshot he talks about the Decepticons like he admires them. Skydive says the Decepticons are well built and resourceful, whilst Slingshot thinks they're superior to humans in just about every way. Silverbolt tells him the Decepticons are also evil -what about the people they dumped? Slingshot says it might have been an accident.

Ironhide thinks they're a bunch of arrogant young punks, and if they had been fighting the Decepticons for as long as they had... Optimus Prime says that's the point -the Aerialbots were only created a few weeks ago. But he thinks they'll understand soon enough. Just then, Teletraan I sends out an alert, warning of potential Decepticon activity. The computer has picked up extremely concentrated energy readings from Cybertron, but the nature of the energy is unknown. Wheeljack points out the high energy readings, and Prime says he's never seen anything like it before.

Prime says they need to go to Cybertron to check it out, so Omega Supreme is summoned. Slingshot is excited that they get to go back to Cybertron, as he and the other Autobots board Omega, who then blasts off.

At the Decepticon HQ, Starscream helps repair Skywarp, when Megatron walks in and chews them out for losing to the Aerialbots. As long as the Aerialbots live, his supremacy of the skies is threatened. Soundwave then contacts Megatron and tells him that the Autobots have departed for Cybertron. Megatron realizes that the Autobots must have detected Shockwave's work on the kronosphere. When Soundwave reports the Aerialbots are possibly there, Megatron thinks he may yet be able to destroy them, and says to have the space bridge activated.

Megatron, Starscream, Thundercracker and Skywarp use the space bridge to get to Cybertron. Starscream asks what the kronosphere is, and Megatron tells him it's a time machine. He'd planned to use it to travel to the past, and steal energy from before the war, when Cybertron had plenty of power. But now, it'll make a perfect trap for the Aerialbots.

Omega arrives on Cybertron and transforms. He tells the Autobots the trip was long, and his fuel reserves are low. Prime tells him to shut down, they'll try to scrounge up some energy for him. But first, they've got to track down those Decepticon energy readings. The Autobots transform and move out, but as the Aerialbots fly, they think the Autobots are weird -why waste their time on the messy, organic Earth when they could hang out here on Cybertron? Slingshot begins to think the Decepticons have the right idea, but Silverbolt thinks his team are nuts -the Decepticons are nothing but trouble!

Just then, Starscream Thundercracker and Skywarp show up, and start firing at the Aerialbots. But most of the Aerialbots don't want to fight -as they transform and land, Slingshot says they just want to talk for a minute! Skywarp thinks they're crazy, and Starscream thinks they are either crazy, or even dumber than he suspected. But he transforms and lands, and tells his new buddies that they'll talk -what do they want to know? Slingshot wants to know why Optimus Prime thinks they're evil.

Starscream calls Prime an old rust bucket who doesn't know a thing about Decepticons. He tells the Aerialbots to stick with him, as he'll teach them some things about the Decepticons all right. Silverbolt can't believe what's happening and contacts Optimus Prime. He tells him that the other Aerialbots are going off with the Decepticon jets.

Ironhide thinks the little twerps are trying to switch sides, but Prime says 10 to 1 they are walking into a Decepticon trap. Starscream leads the Aerialbots towards a certain building, telling them that they'll see that the Decepticons are a swell bunch, and they have fun. Megatron is waiting inside, and thinks it's incredible how naive the Aerialbots are.

As they get inside, Starscream tells the Aerialbots to have a seat over there, as he'll tell them more. But as they do this, they don't realize they are on the kronosphere. Silverbolt runs in and tells his team not to, as this is some kind of a trap, but as he walks into the kronosphere, Megatron activates it.

The Aerialbots are trapped in a pink sphere, and as the kronosphere is turned on, Megatron says that in two minutes, the kronosphere will take them back to the beginning of time! The Aerialbots and flung into the past, and Megatron says they'll be trapped in eternal nothingness forever, before the galaxy even existed!

Just then, Prime and the Autobots arrive, and a battle begins. Having heard what Megatron said, Prime says there is only one way to stop that machine before it takes the Aerialbots back to the beginning of time... and that is to destroy it. He fires at the kronosphere.

His shot hits the kronosphere, blowing part of it up. The Aerialbots arrive on a planet, and wonder where they are. Back in the present, Megatron tells the other Decepticons to get out of here, so they retreat.

As Ironhide says so much for the Decepticons, Prime says now they've got real trouble. The Aerialbots are now trapped somewhere in the distant past of Cybertron, and from these coordinates, he'd says they've gone back nine million years. He says the only hope of getting the Aerialbots back is to repair the kronosphere. Wheeljack says he supposes it could be done, and he and the others get to work. Ironhide says the Aerialbots are in a time before the war, during the golden age of Cybertron.

The Aerialbots wonder what this place is, but realize it's Cybertron, in the past, before the war. Silverbolt says it's before the Decepticons wrecked it, but Slingshot still doesn't buy that story about everything being the Decepticon's fault. After all, the Autobots did their share of fighting. Silverbolt tells him it was because the Autobots had to, not because they wanted to. And it's because of the Decepticons that they're now stuck here! Slingshot doesn't think this place is that bad.

As they head up to a storage building, a worker walks out and asks if they are here to help. Silverbolt says not exactly, as the robot says he's never seen them around before. He says his name is Orion Pax, so the Aerialbots introduce themselves to him. He tells them that they unload the energy shipments from the power plant up river, and takes them inside the building. They see lots of robots unloading energy packs and moving them out.

Dion, Orion's best friend, drives in and transforms. He jokes that it looks like Orion is suckering more people into doing his work for him, just as Aerial appears. Orion says to keep away from her, as she is his girlfriend, but she says not to listen to him -he's just the jealous type! Dion then tells Orion to look, so they head out.

Dion has spotted some new type of robot that can fly. Everyone has heard of them, and it turns out the flying robots are actually Decepticons: Megatron, Shockwave and Soundwave. The Aerialbots of course know who they are, but Slingshot thinks this would be a great time to get to know them. Silverbolt tells him he just has to learn things the hard way, doesn't he? Fireflight thinks they should take cover before the Decepticons attack them, buy Skydive tells him they are in the past -Megatron doesn't know who they are. Fireflight wonders how Megatron couldn't know who they are, but Skydive says this is millions of years ago -they haven't been built yet!

Orion says what he would give to meet them... but Silverbolt walks up and says just because they have an unusual ability doesn't necessarily make them someone he'd want to know. Dion thinks he should go and get his circuits checked, as the Decepticons are the greatest. Aerial says she's heard the Decepticon's leader has put together some kind of army and attacked one of the outer cities, but Dion says she'd believe anything. Orion says what do they care if there is a war -the guardian robots are there to take care of stuff like that. But right now they've got fuel to unload, so the group split up and he gets back to work. He starts to guide a boat in.

But as he does, Megatron appears behind him. He says hello and introduces himself, and shakes Orion's hand. Orion says it's a real thrill to meet him. Megatron shows him a batch of vehicles that all belong to him, and says he has been looking for a place where he can store them. He was hoping that this hangar might be available.

Orion takes Megatron inside, where Dion and Ariel see them. Megatron asks what is stored here, and finds out that it's energy. Megatron says that was just what he wanted to hear, and orders the Decepticons to attack!

Outside, the cargo of the trucks transforms into robots, and then the trucks themselves transform. Orion tells Megatron he can't do this, but Megatron just tells him to get out of his way, and then shoots him.

Aerial yells to leave Orion alone, but as she runs over, Megatron shoots her down. Orion manages to get back up and calls Megatron a monster. He leaps high into the air, but as he comes down, Megatron shoots him again.

Megatron orders his troops to deactivate the rest of them, and then take the fuel. Dion and the other works are shot by the Decepticons. A short time later, the Aerialbots run into the hangar, but see they have arrived too late.

Back in the present, Megatron tells the Decepticons they need to strike back, as if the kronosphere falls into the hands of the Autobots, it'll be a disaster. Shockwave then calls them all over to what he's found: a broken guardian robot. Skywarp says these things give him the creeps, and Thundercracker remembers how they used to give them a pounding back in the old days.

Megatron asks if it could be reactivated, and Shockwave says possibly, but a lack of head will maneuverability. Megatron says a warrior doesn't need a head -just a good, strong body.

Nearby, the Autobots are still working on the kronosphere, but Wheeljack says it's still going to be a while before it's ready. He says the kronosphere has an automatic recall, so at least it'll be able to bring the Aerialbots straight back here -if he can get it working. Prime just hopes the Aerialbots haven't got into too much trouble -wherever they are.

Back in the past, the Aerialbots carry Orion, and Slingshot says they've got to find someone who can repair him and his friends. And that Megatron... he'll pay him back for this if it's the last thing he does! Silverbolt reminds him he wanted to be pals with Megatron earlier, but then another robot calls out to them. It's Alpha Trion, who says if they want to repair that robot, they should take him to the next city. Slingshot asks if he can help.

Alpha Trion tells them to look inside, as the wounded have been pouring in since this morning. He had been developing a way to rebuild their robots to fight the Decepticons, but now... Silverbolt asks if he could please just take a look at Orion, so he does. He says he does detect a strong spirit within him.

He decides to attempt to rebuild him entirely, and Fireflight says he wasn't the only one -there are others back at the hangar, like Orion's girlfriend, Aerial. Alpha Trion says it'll have to be one at a time, perhaps he can help her too -if his plans work. He takes Orion and heads into his workshop with him. Meanwhile, the Decepticon's advance is halted...

...by the arrival of some guardian robots, which cause them to fall back. The Aerialbots wait around for Alpha Trion to finish, and he then opens the doors. He says he's finished, but they may not recognize Orion now, as he is no longer Orion Pax. Now, he is the first of their new defenders...

...Optimus Prime! Prime tells his friends he was wrong -he admired Megatron because he was powerful, and failed to see how he used that power. Slingshot says it's OK, as they've all made the same mistake. Fireflight says they've got to try and help Aerial, and Prime asks Alpha Trion if he can reconstruct her as he did him.

Alpha Trion says perhaps he can try a similar reconstruction using Prime's schematics, and will send some droids out for her. Prime tells the Aerialbots they can go and stop Megatron, so they head off. As they leave, Alpha Trion ponders about creating a female warrior... he'll call her Elita One.

The Decepticons are making gains -defeating a guardian robot by destroying its head. Megatron orders his forces to destroy the guardians, but Prime appears and says he's caused enough destruction for one day.

Megatron says he hasn't even started, and shoots him. But his blasts have no effect and he demands to know who he is. Prime tells him he is his worst nightmare.

Megatron tells his troops to attack him, only for them get blasted to bits. Meanwhile, the Aerialbots head back to the hangar, where they see lots of Megatron's transport drones heading in to get the fuel. Skydive says if Megatron gets that fuel now, he'll be unstoppable. Silverbolt tells him that's why they've got to make sure he doesn't get it.

Back in the present, Wheeljack and Ironhide finish off the repairs to the kronosphere. Wheeljack says the Aerialbots will be back in two minutes, but then Megatron and the Decepticons attack. Prime tells the Autobots they've got to keep them at bay until the Aerialbots get back, but then things get worse when the headless guardian robot crashes through a wall, and heads towards them.

Back in the past, the Aerialbots have shuck into the hangar, and have set up several energy packs next to a massive pile of energon cubes. Silverbolt says they'll wait until all the drones are inside, then blow it up. But Skydive points out that a load of Decepticons are now blocking all the doors -there's no way they can get out of here before those fuel stockpiles explode. Silverbolt says they can't let the Decepticons win.

Slingshot agrees, saying that if the Decepticons win this battle, they'll win the future. Silverbolt tells him to do it, so he fires at one of the packs, setting off a chain reaction that causes several large explosions, each one getting nearer and nearer to the energon and the drones.

But before the Aerialbots can be caught in the blast, they are transported back to their own time. The hangar explodes, and then, millions of years later...

The Decepticons are still fighting the Autobots, but as the guardian robot moves in, a bright light appears between it and the Autobots. It's the Aerialbots, who run out guns blazing.

They transform and unite into Superion, and after a brief struggle, he reduces the guardian robot into a bunch of wrecked parts. The Decepticons flee...

...as Slingshot yells at Megatron that he'll never get away from them -they won't stop fighting until he's finished. The Autobots head outside, and Silverbolt present Prime with some energy packs they brought back with them -enough to give Omega Supreme enough power to take them home. Wheeljack asks what happened to them in the past, and Silverbolt says not much. They learned a few things about Megatron, and Optimus Prime... or should he say Orion Pax?

Prime then realizes something -it was the Aerialbots who saved him! Ratchet asks what this is all about, but Silverbolt tells him to ask Prime -he knows. Prime says it all began about nine million years ago... to which Ratchet moans that it's going to be one of those long stories...

NOTES

-It was mentioned in The Search for Alpha Trion that Alpha Trion was Optimus Prime's creator, and this was mentioned again in the second part of The Key to Vector Sigma. This episode actually shows how Optimus Prime came to be.

-Alpha Trion is never named in the episode. He has a slightly different design when compared to his previous appearances.

-Thundercracker and Alpha Trion were usually voiced by John Stephenson, but for this episode, Alpha Trion was voiced by Corey Burton, whilst Thundercracker's single line was provided by voice director Wally Burr.

-This is one of the most violent episodes of the series, with:
--Orion getting shot twice, the second blast going right through him.
--Aerial being blasted, with a load of smoke coming out of her.
--Dion and some other generic robot being gunned down.
--A guardian robot being shot in the head, which causes its head to explode (this is the one I'm amazed was allowed to air).
--Prime gunning down several of Megatron's troops, with each one exploding when hit.
--Superion hitting the guardian robot with enough force it breaks apart into pieces when it lands.

-Despite the above, writer David Wise has said in an interview it was originally even more violent -when Megatron shoots Orion for the first time, what was supposed to happen was his blast would have severed Orion's arm. Megatron would have then picked the arm up and used it to decapitate Orion! This bit was changed so Megatron shoots Orion through his chest.

-Another difference is that Aerial was originally supposed to die. But when David Wise was informed about Elita One, he changed the script to make it so Aerial would be reconstructed into Elita.

-Fans have speculated what happened to Dion, with some believing he was rebuilt into Ironhide. Others believe was rebuilt into Ultra Magnus (a character who will debut in the Transformers movie, who Prime refers to as his "old friend"). However in 2010 Hasbro themselves gave an official answer: Dion is dead.