Trudging through the Arctic, Bulkhead and Bumblebee locate a huge pod buried in the snow. They take it back to base, where their systems are checked over by Ratchet. Optimus asks about the pod, but Ratchet says it can't be opened while it's still frozen. Even as it sits defrosting in another part of the base, the pod cracks open from the inside.
Optimus and Arcee prepare to travel to the Arctic to look for more clues regarding the pod's origins, and Ratchet gives them some temperature sensors so they can tell when their core temperatures drop to dangerous levels. The kids arrive in time to see them off, and Jack's initially keen on going with them, until he finds out where they're headed. Raf's still interested in seeing some snow, but Optimus says the conditions are too harsh. No sooner have Prime and Arcee stepped through the Ground Bridge than the Ground Bridge system goes down. While the Autobots start trying to repair it, Jack and Miko start playing video games and Raf wanders off. He's playing "being in the Arctic" in a corridor when he stumbles on a tiny, cute metal critter. He plays fetch with it using a bolt... which it promptly eats. Happy with his new pet, he heads back to the control room, unaware that there's a sparking hole in the equipment behind him.
Ratchet's just dug out a damaged Ground Bridge component when Raf returns with his find. The Autobots react in terror to the tiny critter. The kids are surprised at the reaction to what the Autobots are calling a Scraplet, but then the creature starts chowing down on Bumblebee, and Raf has to beat it to death with a crowbar. Ratchet's suspicions as to the Scraplets’ origin are confirmed when they check the Arctic pod and find it's been broken open: thousands of Scraplets now infest the base.
In the Arctic, Optimus and Arcee find their core temperatures have dropped into the danger zone, but Optimus is unable to contact the base to request use of the Ground Bridge.
Meanwhile, Ratchet discovers that the Scraplets have broken the comm system. Bulkhead's in favor of bugging out, but doing that will mean certain doom for Optimus and Arcee. After hearing Bulkhead's detailed description of what Scraplets can do to a 'bot, the kids volunteer to help. Since the Scraplets aren't interested in eating humans, they pair off with the three Autobots, Jack helping Ratchet repair the Ground Bridge while the others hunt for the Scraplets. Miko and Bulkhead explore the corridors where Raf saw the first Scraplet, and after an embarrassingly girly scream and an encounter with a bunch of overhead cables, Bulkhead is set upon by the little monsters. Elsewhere, Raf and Bumblebee likewise run into a group of the things. Ratchet has meanwhile finished repairing the Ground Bridge, but it still refuses to function. As he investigates further, a swarm of Scraplets enter the main control room via a vent and begin flying overhead. They attack Ratchet, but Jack uses a nearby fire extinguisher to freeze them off. There are more of the pests flying overhead, however, and as the others return from their search, the Scraplets attack and overwhelm the Autobots.
While Arcee and Optimus try to keep themselves conscious and functional by talking, the kids manage to eliminate the Scraplets attacking their friends. However, from the sounds elsewhere in the base, it's clear there are many more lurking about. They come up with a plan to send the Scraplets to the Arctic by getting the Ground Bridge working, and Ratchet works out there must be an Energon fuel line breach preventing the system from starting. The three kids take a tool kit and go to fix the breach. They're just finishing when the Scraplets decide it's time for lunch and break into the main control room.
Back in the Arctic, Arcee bemoans the frozen death that apparently awaits her and Optimus, especially after all they've survived so far. Optimus offers what words of philosophical comfort he can, and she says it's an honor to serve with him.
At the base, the kids rush back to the command room and let Ratchet know that the Ground Bridge is back online. He opens the Bridge to the Arctic before collapsing, and Bulkhead acts as bait, leading the Scraplets through. He arrives in the Arctic to see Optimus and Arcee staggering towards the Bridge, and the Scraplet horde bursts through behind him. Optimus braces for the attack, but the Scraplets rapidly freeze in the air and bounce harmlessly off him.
Back at base, Ratchet supervises repairs on Bumblebee and Bulkhead. He and Optimus pay tribute to the strength of their human allies, but just then, Miko spots a spider and runs away screaming.
* AbortedArc: Arcee decides to blame Bulkhead for her and Optimus' predicament, and Optimus tries to defend the big guy despite his clumsiness. Bulkhead comes through and saves the entire group, but Arcee isn't seen thanking him, and the subplot is just left hanging.
* AFatherToHisMen: Even when nearly frozen to death, Optimus doesn't hesitate to stand in front of Arcee to protect her from the onslaught of Scraplets.
* BewareTheNiceOnes: When his new pet turns on Bumblebee, Raf beats it into submission with a pipe.
-->'''Jack:''' Easy there, killer.
-->'''Miko:''' Whoa. I did ''not'' see that coming.
* ByTheLightsOfTheirEyes: The lights briefly go out, and you can see only Miko and Bulkhead's eyes (along with Miko's [[PrehensileHair ponytails standing up on end.]])
* FinalSpeech: Well, Optimus and Arcee think it is, anyway.
--> '''Arcee:''' You know the worst part? After battling 'Cons all these years - smacked down, shot at, blown up - this is how our lights go out?
--> '''Optimus:''' Arcee, this may not have been the finish that we had planned. But if this is indeed the end - if we are to become one with the Allspark...
--> '''Arcee:''' [[ItHasBeenAnHonor It's been an honor]] serving you, Optimus Prime.
* HoldingHands: A platonic version. Optimus and Arcee hold hands when they believe they are going to freeze to death in the Arctic.
* HypocriticalHumor: Miko ''freaks out'' over a tiny spider where she had earlier teased [[ScreamsLikeALittleGirl Bulkhead]] for his fear of Scraplets. The difference is that Bulkhead has a geniune reason to fear Scraplets: they're ''lethal''.
* IAmAHumanitarian: Scraplets will eat ''anything'' made of metal. But their favorite type is ''living'' metal - like Cybertronians.
* IronicEcho: Miko asks Bulkhead, "Did you just scream like a little girl?" At the end of the episode when Miko runs screaming from a spider, Bulkhead asks, "Did she just scream like a little girl?
* ItHasBeenAnHonor: Arcee tells Optimus this when they believe they were going to die.
* KillerRabbit: The Scraplets may look cute and harmless but the second they see metal...
* MonsterOfTheWeek: The entire conflict of the episode revolves around the newly-introduced Scraplets, and while [[Recap/TransformersPrimeS2E3OrionPaxPart3 other Scraplets do show up]] (and demonstrate just how deadly the things can be), these Scraplets are never seen again.
* ScreamsLikeALittleGirl: During a search for Scraplets, Bulkhead does this when the lights briefly go out.
-->'''Miko:''' Did you just scream like a little girl?
-->'''Bulkhead:''' No! Maybe. Can we talk about this later?
* ScrewThisImOuttaHere: Bulkhead suggests abandoning the base in light of the Scraplet infestation and Bumblebee agrees.
* [[WhyDidItHaveToBeSnakes Why Did It Have To Be Scraplets?]]: Bulkhead is particularly spooked by the Scraplets - to the point of wanting to flee. Bumblebee is also terrified and Ratchet too is jumpy, with good reason.