Astrotrain is flying towards a certain planet, and has to get through an asteroid field to do so. He notices that the planet has a large Autobot symbol on it. Starscream says that their sensors show no sign of life, but Megatron says they must be cautious -the Autobots down there could be deceiving their sensors.

The Decepticons land and start to look around a city, but find that it looks like a ghost town. Megatron finds it strange, as it's not like the Autobots to leave a whole city to decay. They come across a monument, which is covered in inscriptions, but Starscream says it's too bad none of them can read ancient Autobot. He starts messing around with a computer console, and Megatron tells him to get off it as it could be a trap, but he says it's a prehistoric communication device.

He activates a hologram, which shows a rust-covered Autobot. The Autobot gives them a warning -telling them that if they're from Cybertron, they must go. Otherwise they will end up like them -rusted, and then all turned to dust. As the hologram disappears, Rumble and Astrotrain take the warning seriously, but Megatron tells them to be quiet -it was an obvious trick, designed to scare them off. Starscream says Megatron is right -if there's a curse at the door, then there is treasure on the other side.

They head into a building beyond the monument, and come across an object sat on an alter: a lightning bug. Starscream and Rumble try to make it work, but can't budge it. But Megatron tells the weaklings to stand aside, as he has a go. After a few seconds of tugging he makes the lightning bug activate, which sends out a powerful blast.

It destroys the ceiling and heads up into the sky. Megatron says it's ironic -the Autobots will be destroyed by a weapon that they created. The Decepticons leave the city, and head back to Earth.

As Astrotrain passes by the asteroid field, one of the asteroids starts following him. Megatron decides to give it a blast of lightning and fires upon t, causing the asteroid to blow up.

But it sends shards everywhere, several of which hit Astrotrain, and one even goes through him. The shard hits Megatron in his chest.

He tells Astrotrain to return to Earth. The Decepticons arrive back at their HQ, and Starscream tells Megatron that Astrotrain will be laid up for weeks, until replacement parts are manufactured. Megatron tells him to forget Astrotrain and attend to him. Starscream takes a look and says that he's got a nasty tear in his shoulder. Megatron tells him that's a brilliant observation, and demands he removes the asteroid chunk out of him.

Starscream changes one of his hands to a pincer, and after some struggling, manages to remove the chunk. Starscream says unfortunately the operation is a success, and as Megatron tells him his humor escapes him, he notices something -the area the chunk hit him is covered in something. Starscream says it looks like rust. Megatron thinks that's ridiculous, as they are rust-proof, but Starscream thinks he must have been made of shoddy materials. Megatron thinks that's absurd.

At New York City, Perceptor is being awarded the national scientific achievement. He's won it for his invention of corrostop, and he tells the crowd that this is an honor and privilege. He says his plan is to cover all of the Earth's great monuments with corrostop, as it will help preserve them forever. Corrostop resists rust and corrosion, and is stronger than any known metal. However, at this time they only have enough corrostop to cover one monument, which will be the Statue of Liberty. Corrostop is also alloyed from a very rare element, so they don't want the formula to be discovered by the Decepticons.

Back at the Decepticon HQ, Starscream tells Megatron that he's just checked with the repair bay, and his replacement part will be ready as soon as they get around to it. But Megatron doesn't turn around, and says replacing his chest won't be enough. Nor will Starscream's minimal knowledge. He needs an expert, and orders for the Stunticons to seize Perceptor and bring him here. Meanwhile, the Aerialbots head towards the Statue of Liberty.

The rest of the Autobots are already at the statue, covering it with corrostop, and have a truck load of the stuff. Meanwhile, the Stunticons are on a ferry, heading towards the statue.

They transform and Breakdown says this is mutiny... no, it's a hijack... he means they are taking over this boat! He tells everyone to snap to it, and has them head inside the boat, where he locks them in. Meanwhile, Perceptor is being interviewed about the corrostop. He says it will keep the statue safe from acid rain, or anything else that's harmful.

The news reporter asks about how he came up with the formula, but he says he can't reveal anything about the compound. Just then, Wildrider leads a water-skiing Drag Strip towards dry land. The news crew flee as Drag Strip transforms and starts firing at Perceptor.

Perceptor is chased towards the sea, at which point Motormaster wraps a chain around him and uses it to drag him into the water. As he cries out for help, Optimus Prime and Ironhide are looking at the statue, as Prime says the job is almost finished. The news reporter runs up and says Perceptor has been captured.

Prime orders the Aerialbots to transform and find him, so they take off. Perceptor is taken away and put in Blitzwing, who takes off and heads back to the Decepticon HQ. But the Aerialbots see him, and go after him.

As they get to the Decepticon HQ, Dirge and Ramjet appear and have the lightning bug ready. They use it against the Aerialbots, hitting Fireflight with it first. Air Raid fires off several missiles...

...but these all get destroyed before they can hit their target, and Air Raid then gets blasted. The Aerialbots decide to return to the Autobot HQ, leaving the Decepticons to take Perceptor to Megatron.

Megatron welcomes Perceptor, but coughs as he does so. Perceptor tells him to dispense with the formalities, as Megatron is his mortal enemy, and... Megatron then turns around, revealing the horrid state the rust has left him in.

As Dirge and Ramjet look on in horror at what has become of their leader, Megatron tells Perceptor he has a unique opportunity to gain peace, in return for a favor. Perceptor asks what the favor is, and Megatron tells him to solve this little problem he has. Perceptor says if he's serious, he must surrender his new weapon. Megatron says if he cures him, he can have the weapon.

Perceptor transforms and takes a look. He finds that Megatron has been infected by a metallic plague. Megatron says that's impossible, as only organic forms of life can be infected by disease. Perceptor says it's a rare metallic infection, and legend has it that it wiped out entire races of robots -it's cosmic rust. He is given the asteroid chunk that Starscream removed earlier, and says it's what caused the problem. This asteroid is covered in cosmic rust germs, and the germs have been feeding off an alien energy source.

He says that source is the lightning bug, which is making the disease spread faster. He wants to destroy it now, before he tries to cure Megatron, but Megatron says this wasn't their agreement. As he starts shaking his fist, demanding to be cured now, his hand falls out of his arm! Megatron tells Perceptor now look what he's done.

Perceptor picks up the hand and says perhaps a few drops of this will help. He starts covering it with corrostop, which gets rid of the rust. He explains to Megatron what it is, but Megatron snatches the vial and uses it to cover himself. He tells the Decepticons that they're about to be cured.

Up in space, Cosmos and Blaster and heading back to Earth. Cosmos tells Blaster he has something terrible to report: there is no more ingredient X anywhere. Blaster thinks Prime will really have the blues when he hears this news, as there's nowhere to shop for more corrostop! At the Autobot HQ, the Aerialbots explain to Prime about what happened.

Air Raid and Fireflight show how they got sizzled by the heat ray, and Prime says this is grim news indeed. Megatron then contacts Prime, and tells him he comes to him with a gesture of goodwill. Prime finds that hard to believe, but Megatron says he is releasing Perceptor. He'll leave him in a canyon which is only three miles from the Autobot HQ, and he's there now.

He tells Prime to pick Perceptor up by noon, as if he doesn't, the sun's rays will focus through his lenses, which will ignite the fuse of the bomb left at the base of his microscope. Prime gathers all the Autobots outside, and says he's sure they're all aware they will be heading into a trap. But they must go, otherwise they'll lose Perceptor forever. They Autobots transform and roll out, but as they arrive at the valley, there isn't any sign of Megatron. Prime tells the Autobots to stay back, as he goes in.

He gets to Perceptor, but Perceptor warns him that he'll be infected with cosmic rust. Prime says if he doesn't save him, the bomb will blow him to bits. He removes the straps and frees Perceptor, as the two Autobots run off seconds before the bomb goes off.

Perceptor tells Prime to leave him here, as if he goes back to their HQ, he could infect everybody. Prime refuses to leave him and takes him back to their HQ. Perceptor explains about the rust germs, and how they devour Cybertron alloys. Prime wonders where the germs came from, so Wheeljack uses Teletraan I to find out. Teletraan I states that the germs originated on a planet called Antilla.

At the dawn of time, there was a thriving Autobot civilization on Antilla, but then some dreaded asteroids began falling from the sky, hitting the cities and spreading cosmic rust. No cure was ever found, and the Thirteenth Legion -also known as the Lost Legion -was decimated by the malevolent scourge.

Prime says the plague has now spread to the Earth. Wheeljack asks if there is anything they can do to protect themselves, and Teletraan I says corrostop is the only known antidote. Prime says they can't make any more, as they are out of the secret catalyst. Wheeljack suggests using the matter duplicator, but Prime says the duplicator has never worked. He then notices Teletraan I is malfunctioning, and tries to fix it, but then notices his hand is showing signs of cosmic rust.

Some of the other Autobots are also getting rusty, and Ratchet says it seems to be getting hot in here. That's because outside, Megatron is hitting the Autobot HQ with the lightning bug. Rumble asks why he doesn't use it at full power, to melt the HQ to the ground. Megatron tells him he wants to let the Autobots suffer slowly. Soon they'll all be nothing but rusted scrap!

Prime says Megatron must be using that ray to spread the germs, so Perceptor says there is no time to lose. He manages to get up, and tells Wheeljack that they have work to do. They head off to the matter duplicator, and try to get it to work. Perceptor manages to "fix" it by giving it a good kicking...

...and the duplicator manages to duplicate the compound. At the Decepticon HQ, Soundwave reports to Megatron, saying that Laserbeak has returned with the visuals. They watch the recorded footage, and Megatron is pleased to see so many Autobots lying around rusting. Bumblebee says someone has to get them back to Cybertron, and he never thought the end would come like this. Just as Megatron tells Prime to rust in peace, Perceptor is seen walking in, saying they've done it and they'll be saved -the matter duplicator works, so now all they need to do is scrape some corrostop off the Statue of Liberty, then they can mass produce it.

Megatron says they must hurry, and heads off to the statue with Soundwave and Rumble. As they arrive, the Stunticons are also present on their boat. Megatron tells them to transform and merge into Menasor, who he then says will have the honor of firing the lightning bug's heat ray at the statue.

Menasor picks up the lightning bug and is about to use it, but Prime tells him to drop it. Prime and the Autobots appear on the statue, and Prime tells Megatron to retreat now, but Megatron asks who will make him. He and the Decepticons start firing...

...as the Autobots fire back, and a battle begins. Megatron tells Menasor to turn on the heat, but before he can, the Aerialbots attack him and make him drop the bug. They then transform and unite into Superion.

Superion and Menasor battle each other, with Superion eventually winning by throwing Menasor so hard he falls apart into the individual Stunticons.

Superion then shoots the lightning bug, destroying it. Megatron tells the Decepticons to abandon their position and fly out. As they retreat, the Stunticons follow them.

Prime says he thinks they've seen the last of cosmic rust. And Bumblebee says they saved the lady at the same time. When Prime asks about the lady, Bumblebee points to that one: the Statue of Liberty.

NOTES

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