Megatron brings Cybertron into Earth orbit to harvest the energy from the destruction caused by Cybertron's gravity.
- Japanese title: "Day of Destruction - Part 1"
- Russian Tv dub title (6th channel): "Окончательное уничтожение. Часть 1" ("Final destruction. Part 1")
Starscream, Thundercracker and Skywarp attack a solar power station on India's coast. Optimus Prime, Wheeljack, Jazz and Sunstreaker arrive in time to intercept them. Watching this battle remotely are Megatron and the evil human scientist Doctor Arkeville. Megatron orders Soundwave to begin phase two of Operation Guinea Pig, which involves setting Rumble and Ravage loose inside Autobot headquarters. With the Autobots distracted by Rumble's rumbling, Laserbeak flies in, nabs Sparkplug and flies out.
Back in India, the Seekers suddenly take flight and retreat. Prime smells a rat, then Sunstreaker tells him of the attack on their headquarters.
After bringing Sparkplug to Decepticon headquarters, Doctor Arkeville fits him with a mind-control device called a hypno-chip which brings him into the Decepticons' control. Megatron intends to use this technology to create an army of human slaves. With the successful completion of the first part of his plan, Megatron communicates with Shockwave to confirm that the new space bridge is ready.
The Autobots attack the Decepticon undersea base to rescue Sparkplug. Optimus Prime leads a direct attack from above while Cliffjumper, Brawn and Windcharger tunnel under the ocean floor. The mission is successful, and the Autobots return him to their base. After undergoing repairs, the Autobots and Spike notice that Sparkplug is acting oddly, but before they can learn why, the Decepticons launch a surprise attack. Spike realises that Sparkplug has sabotaged the Autobots' weapons and Teletraan I, which let the Decepticons in undetected.
When Spike confronts his father, Sparkplug appeals to Spike to join the Decepticons. Spike refuses, and Sparkplug tells his son that when they next meet, they will be enemies. In a desperate effort to salvage the situation, Spike sets off the fire-retardant foam. This clogs the Decepticons' weapons, and Megatron orders a retreat. Sparkplug willingly goes with them.
At the space bridge site, Megatron reveals that he intends to bring Cybertron into Earth orbit using the bridge. The gravity of Cybertron will cause natural disasters, and the Decepticons plan to harvest the energy and transport it to Cybertron. Arkeville isn't too keen on this idea, but Megatron says it's a new problem for the evil scientist to solve using his genius intellect.
Using the Sky Spy, the Autobots see the giant space bridge and roll out to investigate. When they attack the bridge site, Megatron releases a group of human slaves to act as shields. The ploy works, and things get even more complicated when the humans attack the Autobots with sticks and stones.
Spike stops Sparkplug from attacking Bumblebee, and for a moment it appears that Sparkplug is back to normal. But Arkeville recomputes his signal, and Sparkplug is again under Decepticon control. He rushes to the first space bridge pylon and activates it. Thundercracker activates the second.
Optimus Prime chases Megatron up to the third pylon and wrestles him away from the button. Megatron orders Prime to turn on the pylon himself, or else he will be responsible for catapulting Cybertron into oblivion. Unwilling to sacrifice his home planet, Optimus Prime activates the space bridge, bringing Cybertron into Earth's orbit, but wonders if he is dooming Earth in the process.
Original airdate: November 3, 1984
Written by: Larry Strauss
(Numbers indicate order of appearance.)
"Laserbeak, where are your manners? Our guest needs a seat."
- —Megatron kicks a chair toward his captive, Sparkplug.
Skywarp: "I say Megatron's plan was brilliant."
Starscream: "And I say the diversionary attack on the solar plant was a waste of energy."
Skywarp: "You waste more energy with your mouth!"
- —More heart-warming Decepticon camaraderie.
"I've got the plan, if all of you've got the cast-iron manifolds for it!"
"Into the ocean, let's be daring. The last one in is a rusty herring."
- —Jazz comes out with the worst rhyme in the history of the multiverse.
Megatron: "Fire-retardant foam! Our circuitry's been shorted out."
Thundercracker: "My weapon!"
Skywarp: "Can't we just bash 'em to pieces?"
Megatron: "If we stay, this foam will permanently damage our circuitry. The Autobots are through anyway. RETREAT!"
- — The Decepticons become ever more farcical and ridiculous.
"Have I saved Cybertron...only to destroy the Earth?"
- —Optimus Prime angsts over his decision to bring Cybertron into Earth's orbit.
- This episode is subtitled "Brainwash" in scripts and other official materials.
Animation and/or technical glitches
- When the Autobots roll into action near the start of the episode, Sunstreaker is briefly coloured as Sideswipe.
- Sparkplug's wrench looks different between shots.
- While communicating with Shockwave, Megatron appears to bob and float, rather than remain stationary, as would be expected.
- When Shockwave changes positions while talking to Megatron, there is an outline of his previous position on the screen.
- When the fake Optimus Prime appears at the Decepticon base, Skywarp speaks with Starscream's voice.
- When the Autobots are rescuing Sparkplug, Cliffjumper is colored as Bumblebee.
- When the Decepticons are showered with foam at the Ark, the shot cuts from Thundercracker to Skywarp by simply changing the colors on the character.
- When Starscream flies to the space bridge, his alt-mode is mistakenly colored as Skywarp.
- When the Autobots first see the slaves, there is one brief moment in which Optimus Prime is drawn without his faceplate.
- Megatron's fusion cannon is drawn pretty badly repeatedly throughout this episode. The front barrel is often drawn at less than half the size it should be. (See the picture further up this page for an example). Apparently size isn't important after all.
- The Decepticons can be apparently easily damaged by fire-retardant foam, yet the Autobots are fine.
- Spike trips over a wrench and goes sprawling on the floor of the Ark. In order to have tripped Spike, the wrench must be either monumentally heavy or bolted to the floor; nonetheless, in the next frame Spike picks the wrench up with no sign of strain - just as you would expect anyone could.
- Prowl says to Prime and other Autobots standing nearby, "I've got the plan if you all have the cast-iron manifolds for it," and Prime asserts that "We have!" Prowl even looks directly at Prime as he says this. Does that really seem like something a strategist would say to his leader, who's proven his courage time and again?
- Perhaps it was part of Prowl's master plan to prod Optimus Prime to immediate action by playing on his courage. Or perhaps Prowl's just a prick.
- Sparkplug was able to survive being on the floor of a presumably deep ocean without a diving suit, and somehow managed to hold his breath until they got back to the surface without getting the bends. Yeah, because that's possible...
- When Megatron orders Sparkplug to attack the moving, life-sized model of Optimus Prime, Sparkplug finds the strength to grab it by the ankle and tip it over.
- The Hypno-Chip is supposed to turn humans into mindless slaves, but apparently it makes Sparkplug evil and/or loyal to the Decepticons.