Sari introduces Bumblebee, Bulkhead and Optimus Prime to the concept of Halloween, starting with selecting pumpkins. As she explains the idea of choosing just the right costume, Prime's attention is distracted by a large black widow spider decoration. He remembers back to his academy days...
On an organic world, Optimus and his friend Elita-1 admire the strange webbing stretching across the high rocks, not knowing what it is, until Sentinel Prime calls to them to hurry up. Optimus cautions about the fact that such worlds are normally considered off-limits to Autobots, but there's supposedly a real Decepticon ship somewhere in the area. Elita's there for the historical value, but Sentinel just wants to get his hands on the energon cache that must be in it. Prime's still wary of potential punishment should they get caught, but figures he has to keep the other two from getting in over their heads. Sentinel insists that never happens—right before the ground crumbles under their feet, sending all three plunging into a deep cavern. Strange, skittering noises echo from its dark reaches. Optimus activates his shoulder-light to see...
Bulkhead snaps Prime's attention back to the present by donning a bedsheet (which just covers his head) and going "Boo," startling his leader. Prime claims a ghost from his past just has him jumpy, then stalks off.
Back at the Autobot base, Sari critiques Bumblebee and Bulkhead's costumes, but says her own costume is only one surprise planned for the night. Noticing Prime lost in thought, she uses her key to activate one of the car plant's cranes, swinging another spider decoration in his face. The unexpected sight of it gives Prime a bad flashback, and he quickly hacks the fake spider to bits. He admonishes Sari for making frivolous use of the All Spark Key, and she counters about him needlessly using his axe. Prime stares down at the remains of the decoration, and his thoughts travel back again...
As Prime, Elita and Sentinel walk through the cavern, Sentinel enthuses about the rich hoard of energon he's sure they'll find soon. Prime shushes him as he hears something, and soon all three are casting their lights about, trying to pinpoint the skittering. The source reveals itself as an enormous, alien spider, which quickly traps Elita with some webbing. As Prime fights it off, Sentinel frees her with his charged shield, but the spider abruptly takes him down. Elita starts using her special power-download ability, but Optimus, holding back the spider, tells her it won't work on organics. She instead borrows the unconscious Sentinel's shield power and shield itself, using them to defend herself, then to bring down a huge stalactite to impale the spider. As Sentinel wakes up and Elita returns his shield, Prime says that it's not worth staying around, be it for history or energon. Sentinel still insists on one good reason to leave, and he gets three when another trio of giant spiders drop down to confront them. Sentinel quickly puts up his shield's energy barrier, covering Prime and Elita's retreat. Prime rolls out, and Elita follows, calling his name...
Prime suddenly becomes aware of Sari calling his name to show off her costume—a costume of him. He doesn't appreciate her vocal impersonation of him, and declines to join the trio on their trick-or-treat outing.
As Sari and the two Autobots progress though a local neighborhood, Bumblebee is a bit spooked by the atmosphere. Sari reminds him it's all pretend...unaware they're being tracked by an enormous spider traveling over the rooftops. As she coaches them through their first actual "trick or treat," Bumblebee spots the spider watching them and freaks out, but it's gone before anyone else sees it. Sari teases him for being more timid than Optimus, but 'Bee protests he knows the difference between a fake decoration and a real giant spider. Listening in from headquarters, Prime has Bumblebee clarify what he saw, then heads out to meet them, advising them to stay put.
Racing through the caverns, Prime reaches the wreckage of a Decepticon warship. Separated from the other two, he heads inside, hoping to find them there. Instead, he finds an impressive stash of energon cubes, just as Sentinel predicted. He also finds an impressive stash of giant spider eggs. As the spiderlings hatch and start attacking, Prime gets stuck on some webbing, but Elita shows up in time to help. As they fight to escape from more full-grown spiders, Prime has Elita borrow his grappler ability. They bring down a huge stalactite through the ship's ruined overhead, grappling their way out as the energon detonates below them. However, Elita's download ability times out just then, and she goes plunging back too fast for Prime to catch her. Sentinel arrives on top of the ship as she plummets into the hold, but knowing the energon is going to blow any second, Prime grapples himself and Sentinel to safety rather than risk going after Elita just then. Once they break the surface, Prime scans for Elita's energy signature, but doesn't find it. A furious Sentinel blames everything on Prime.
In the present, still en route to Sari and company's location, Prime swears he won't let it happen again. Meanwhile, Bumblebee stresses that they have to stay vigilant until Prime arrives—even as Sari is yanked out from under them by the giant spider. Bumblebee quickly cuts Sari free, but as he and Bulkhead surround the spider, it transforms into a female robot who calls herself Blackarachnia. Sari's not too surprised or impressed by her femininity, but it makes a much bigger impression on Bulkhead—right up to the point Blackarachnia stabs him with two of her spider legs, knocking him out. She quickly gives Bumblebee the same treatment, then tells Sari they should go, now that Sari's safe. Sari protests the two Autobots are her friends, and Blackarachnia apologizes, pretending she can't tell which robots are good or bad on Earth. As Sari futilely tries to revive Bulkhead with her All Spark Key, Blackarachnia notes that the organic nature of her venom precludes that solution, since the All Spark doesn't affect organics. She offers to try helping the Autobots if Sari will just hand her the key, but her ruse is interrupted when Prime lassos her legs out from under her. Blackarachnia appears shocked to see him, but quickly frees herself and starts fighting back—using Bumblebee's stingers and Bulkhead's strength. Instead of borrowing any of Prime's powers, though, she judo-throws him across the street, then kidnaps Sari.
Prime desperately pursues the pair across the rooftops. He catches up, stuns BA with a faceful of foam, then grapples Sari free. Despite this respite and Sari's warning, Blackarachnia still catches Prime half-unaware. He fights back, but she dodges him constantly, claiming to know all his textbook Autobot Academy moves. Prime wonders if he knows her, and she berates him for forgetting his friends—even if he remembered Sentinel. Prime is stunned to realize he's facing Elita-1. She finally relates what really happened that day:
Trapped in the ship and surrounded by the spiders, Elita tries desperately to download their abilities. Instead, she is infected with their venom, and it mutates her into a freak, a half-organic, half-robotic being.
Prime realizes that her half-organic nature is what masked her energy signature from his scans. BA sneers that if he'd known and saved her, she'd just have been dismantled and examined on some lab table on Cybertron. Prime reproves her for joining the Decepticons, but she counters that at least she knows where she stands with them. She webs up Prime and snatches Sari's key, certain that if anything can purge her organic half, it can. She plugs it into herself, but the unleashed energies begin causing all organic life in range, including Sari, to wither and sicken. Prime breaks free, but before he can stop Blackarachnia, she grabs up Sari and throws her off the roof. Sari snags a flagpole long enough for Bumblebee and Bulkhead to save her, leaving Prime free to deal with Blackarachnia. She collapses on her own, though. Prime surmises her spark can't survive without her organic half, but she's too weak to pull out the key and stop the reaction. Prime forces through the energy barrier around her and removes it for her, restoring the organic life in the area to normal. As he helps her up, Blackarachnia asks him to go, not wanting to be seen like that. Still calling her Elita, Prime asks her to come with them, promising his group will find a cure, and allow him to earn back her trust. She seems to respond positively, but it's another sham. Blackarachnia stabs him unconscious and leaves, vowing it will be a long time before she trusts another Autobot, especially him.
Later, Prime returns Sari's key. She thanks him and admits he was right—maybe it's time she gave the key a rest. Bumblebee trundles in painfully, still damaged from his fall after catching Sari, and asks if she could use it once more. Bulkhead asks who the bug-bot lady was, and Prime responds it was someone he should never have left behind. Elsewhere, Blackarachnia stands on a rooftop, gazing at the moon and sobbing over her fate.
- Written by: Marty Isenberg
- Directed by: Matt Youngberg, Irineo Maramba, Yutaka Kagawa
- Original airdate: February 16, 2008
(Numbers indicate order of appearance.)
"Beautiful, isn't it?"
"Yeah...what is it?"
"I have no idea."
- —Elita-1 and Optimus Prime admire the webs.
Optimus: Somebody's gotta keep you two walking malfunctions from getting in over your heads.
Sentinel: We never get in over our heads.
[The ground crumbles underneath them, causing them to fall into a cavern. Optimus gives Sentinel a look.]
- —Optimus Prime and Sentinel Prime
Bumblebee: [Bad Slavic accent] Velcome. I am Count Dracubot. I vant to drink your motor oil.
Bulkhead: Hey, guys! I finally found something big enough for my ghost costume.
[Fumes surround his feet, causing Sari to cough]
Sari: Bulkhead, where did you get that sheet?
Bulkhead: It was just draped over some house. Weird place to put a bed sheet.
Sari: Oh, that's not a bedsheet. It's a fumigation tent.
Bulkhead: Really...? What's a fumigation tent?
[As well as the fumes, Bulkhead's feet are now covered in dead cockroaches.]
- —Sari sees the Autobots' costumes.
"I've got a good feeling about this. Any cycle now, we're gonna be overflowing with rich, All Spark-infused, energon-y goodness!"
"Did you really just say 'energon-y goodness'?"
- —Sentinel Prime's speech
tick—er, tic bemuses Elita-1.
Sari: Optimus! Check out my costume!
[Camera reveals that Sari is Optimus Prime]
Sari: [Imitating Optimus] Oh, look at me. I'm Optimus Prime. I'm scared of spiders.
[Bumblebee and Bulkhead chuckle]
Optimus: That's not what I sound like...is it?
Bumblebee: Last chance to join us, Boss Bot.
Optimus: Thanks, but I'll pass. Just be careful out there, all right?
Sari: Don't worry. I'll keep these guys out of trouble. [Imitating Optimus] Transform and roll out!
[Optimus gives Sari a look]
Sari: Couldn't resist.
- —Sari and the Autobots roast Optimus Prime.
Bumblebee: Who are you?
Bulkhead: What are you?
Sari: Duh. She's a girl.
- —The gang meets Blackarachnia.
"This is all your fault!"
- —Sentinel Prime, blaming Optimus for the disaster that happened on an excursion he suggested. Jerk.
"So, who was that bug-bot lady?"
"Someone I never should have left behind."
- —Bulkhead and Optimus Prime talk some heavy stuff.
Animation and/or technical glitches
- Shortly after Sentinel says that he and Optimus should go back for Elita when the Decepticon ship explodes, his nose and forehead are painted silver, like Optimus.
- In the Generation 1 animated series, Elita One was G1 Optimus Prime's paramour. The Animated incarnation of the character refrains from attempting to visually homage the original pink-and-white Elita, instead creating a blue-and-yellow pony-tailed character who bears a resemblance to Elita's earlier (pony-tailed) form, Ariel. Her relationship with Prime is less distinct (it almost appears as if she's Sentinel's girlfriend at one point), with this episode's flashbacks not suggesting any romantic connection between the two, but the present-day scenes suggesting some kind of personal tension (though that could be guilt on Prime's part and anger on Elita's).
- Sentinel Prime is depicted here as Optimus Prime's friend and peer, whereas in all other series he's either been Prime's mentor, a superior officer, or a predecessor. In this way it seems the roles of Sentinel and Ultra Magnus have been reversed from past continuities.
- With this episode, energon cubes make their first appearance in Transformers cartoons since Beast Wars. They look exactly like they did in the Generation 1 cartoon, which even Beast Wars didn't pull off.
- This is the first episode to not feature Ratchet or Prowl.
- In a flashback, prior to Blackarachnia's transformation, a helmet can be seen sitting in a corner of the Decepticon ship. In the present day, she appears to be wearing it, possibly to hide the extent of her transformation.
- This episode makes a point of how Sari has been overusing her key previously, and that it can't be used to cure every TF injury. The writers evidently anticipated that reaction from the audience.
- Referring to himself as "vertically challenged," Bumblebee seems to be over his height complex, which was such a major point in "Total Meltdown".
- Bulkhead's "ghost" costume, with its constant cloud of pesticides at the bottom, coincidentally resembles "Pig-Pen's" costume from It's the Great Pumpkin, Charlie Brown.
- Judging how Blackarachnia can swing from a thread, the Autobots had best take a look overhead.
- This is the first time Sentinel Prime has been fully on screen. When he appeared in Transform and Roll Out, all that was seen of him was his head.
- This episode explains why Sentinel Prime hates Optimus.