A group of Quintessons find out about a power core the Autobots have constructed, which will triple Cybertron's energy reserves. A Quintesson scientist wants to try and take the planet back from the Autobots, and to do that, wants the Trans-Organics to be released. These creatures were created by the Quintessons millions of years ago, but were deemed failures. The remaining Trans-Organics were locked away deep within Cybertron. The Quintessons go to Chaar and lie to Galvatron, telling him that the power core has been constructed deep within Cybertron. A group of Decepticons go to Cybertron and head to where the power core is meant to be, only to find a strange machine.

Galvatron shoots at it, causing the Trans-Organics to be released. They attack the Decepticons, just as a group of Autobots arrive. The Trans-Organics start attacking them as well, so the Decepticons quickly run off to the next room. But there, they find something even worse: the Dweller. Another Trans-Organic, the Dweller is capable of draining the energy from its victims and turn them into energy vampires, which it does to several Sweeps.

The Decepticons go back and the Dweller follows them, where it drains Wreck-Gar. Wreck-Gar then drains Springer, whilst the Dweller drains and destroys the remaining Trans-Organics. Scourge then gets drained trying to escape with the rest of the Decepticons, whilst Kup is drained after saving Arcee. Arcee and Ultra Magnus head back to the surface, as the Dweller and the energy vampires follow them.

The remaining Decepticons aside from Galvatron are drained. Galvatron finds Magnus and Arcee and intends to destroy them before the Dweller gets him, but then the Dweller appears and starts draining him. The Dweller also attacks Magnus, but Arcee takes Galvatron's cannon and uses it to blast the Dweller through a wall. The Dweller senses the energy from the power core, and heads to the surface. Magnus and Arcee make it to the surface first, where they find Rodimus and Perceptor and tell them what's happening. The energy vampires then appear, but Perceptor fixes everyone by running a massive power load through them.

The Dweller finds the power core and latches onto it, so Rodimus orders for the core to be blasted into space. Perceptor does so, and the Dweller ends up finding its next power source: the Quintesson's ship. Back on Cybertron, Perceptor is able to get some emergency auxiliary power, and says that'll have to hold them until they can build a new power core. Arcee tells him that, considering that they're still here, and they got rid of that creature, it's a small price to pay.

Notes

-The Secret Files segment for this episode is about the Decepticons.

-This episode was also adapted into a comic book, but was never actually published. Scans of a few pages from it can be found here.

Errors

-The Quintesson Prosecutor is badly miscolored during this shot.
-After Galvatron takes his first shot at the Autobots, his mouth opens and closes a few times, but he's not heard saying anything.
-Kup is colored like Springer during this shot.
-Ultra Magnus has a Jazz-style visor for eyes during this shot.
-The Dweller's yellow glowing eye effect is missing during this shot.
-The Dweller has a red eye instead of a yellow one when Arcee shoots at it.
-The Dweller's eye is red again when Arcee tries to drive away.
-During Galvatron's "two less Autobots to mourn" line, he's standing up. Magnus then leaps forwards, and then Galvatron is suddenly knocked down already.
-Galvatron's chest insignia is colored red instead of purple when Magnus throws him.
-Parts of Perceptor's chest are colored white instead of red during this shot.
-The red glow effect for Kup's eyes is slightly misaligned during this shot, appearing under his eyes instead of over them.
-When the Dweller reaches Cybertron's surface, First Aid is colored like Eject, Streetwise is colored like Optimus Prime and Groove is colored like Wheelie.
-When the shot changes, Streetwise is colored mostly blue and white.
-The Dweller's glowing eye effect is missing again when it bites down onto the power core.
-During this shot, part of Perceptor's right arm can be seen passing through the computer he's using.
-During the final shot of the episode, the Dweller's eyes are colored red instead of yellow.