History Lessons is the first episode of Season 2 1/2 and the fortieth overall of Transformers: Robots in Disguise.
A revisit to the original Autobot base reveals a dangerous new enemy with an agenda of his own.
As the Autobots prepare to embark through the GroundBridge, Fixit laments that he always misses the adventures the others go on. Sideswipe tells him he hasn't missed much, somewhat annoyed at Bumblebee's enthuiasm about taking his team on a "history lesson". The Bridge opens, and the team steps through...into a human military base, much to Strongarm's panic about their being exposed, and she frantically calls Fixit for a groundbridge out before they're discovered only to be countermanded by Bumblebee, who tells them there's nothing to worry about, and invites them to analyze the surrounding base and tell him what they discover.
Strongarm notes that everything is covered in dust, while Grimlock and Drift observe that whoever had occupied the base before abandoning it had terrible taste in furnishings. Grousing that the base is only abandoned now, Bumblebee leads them outside, where the team scans a nearby abandoned Jeep for desert camouflage colors - except for Grimlock - and they head to where they can get a good look at the surrounding area, where - to Strongarm's wonderment and Sideswipe's annoyance, they see another piece of history: the ruined mesa that once housed Autobot Outpost Omega One.
The team transforms to drive to the outpost, where Bumblebee warns them to be cautious, as they had left security systems operating when they abandoned the base. Waxing nostalgic about days of hiding from invading Decepticons and arm-wrestling with Bulkhead, he muses that they should retrieve some of the "important artifacts" that were stored on the lower levels, levels they had kept secret even from the humans "for their own protection". However his reminiscing about having once kept a holodiary is cut short by Sideswipe's observation that a nearby "historic artifact" looks rather newer than it should be - and it is, in fact, a bomb.
After fighting off the indiscriminate security systems with the help of Jetstorm and Slipstream, Bumblebee calls to have Fixit start work on deciphering the bomb, while the team splits up to try and find who placed it. Bumblebee and Sideswipe head directly down into the base where they stumble across a scorpion-like Decepticon who introduces himself as Paralon, and declares that the base, and everything in it, is his by right of salvage. His partner, the Mini-Con Buzzstrike, transforms into an Energon axe, and the Autobots marvel at the energy reading he's giving off, along with the fact he's powering up Paralon, before Sideswipe runs out of patience and charges. Bumblebee calls for backup as Sideswipe is sent flying, but the call is garbled when the others receive it, and they assume it was a normal check-in.
Elsewhere, Strongarm and Grimlock are exploring when Grimlock steps on something that goes click. Alarmed, the two call Bumblebee for advice, only to find no response. Strongarm starts trying to decide exactly how to deal with what they're certain is a mine - much to Grimlock's discomfiture - as Drift, Jetstorm and Slipstream have their search route take them close enough to detect the sounds and flashing lights of combat, and charge in. Paralon is put on the defensive by Drift - but he throws Buzzstrike at Bumblebee, who catches him, and the Mini-Con immediately interfaces with him, taking control of his body and forcing him to attack Drift as Paralon makes quick work of the samurai's Mini-Cons.
Between them, Paralon and Buzzstrike take down the team; Paralon, worrying that the base could be swarming with Autobots at any moment, observes they don't have time to finish them off as he signals the bomb to accelerate its countdown. Buzzstrike balks, noting he didn't sign up to hurt people; Paralon tells him that anyone who gets in the way of Scavengers has brought their fate on their own servos, and he transforms into scorpion mode, a pensive Buzzstrike climbing aboard as they hurry off to the central command center where they will be safe from the blast. Sideswipe comes to just in time to see them leave, and he decides to follow and take them down once and for all.
Strongarm, meanwhile, realizes she and Grimlock are in over their heads, and she transforms to find Bumblebee to solve the problem, in the process driving by the bomb and noting with shock that it's activating. She finds the others as they come to, and they rush back to the bomb. The interference from earlier is worse now, and they can't contact Fixit for advice; Bumblebee declares there is only one option left, and he activates his Decepticon Hunter and strides towards the bomb while raising the weapon.
Sideswipe catches up with Paralon and Buzzstrike as the scavengers discover a plasma rifle in the wreckage, bluffing that the others are right behind him, only to have his bluff cut short by an earthquake from the bomb's explosion. Recovering, he stuns Paralon, grabs the rifle and transforms, driving back into the base as Buzzstrike looks on thoughtfully.
Back with Bumblebee, Strongarm compliments him on his using the Decepticon Hunter to trigger the force shield trap to contain the bomb's explosion, then tells him that Grimlock needs his help now, leaving Bee to sigh about how the day just keeps getting worse. Elsewhere, Paralon grouches about the base having so many levels, only to be ambushed by Sideswipe, who had ducked into the secret storage levels to hide. The two duel, Sideswipe knocking out the Decepticon once again - only to have Buzzstrike take over Paralon's unconscious body. He offers to let Sideswipe keep the weapon they'd found if they are allowed to go; the hot-headed Autobot counters that he intends to take the weapon and the scavengers in, sparking a fight that Buzzstrike-Paralon quickly wins...only to leave Sideswipe, and the weapon, sprawled on the floor as he turns to walk away.
Bumblebee finds Grimlock, the Dinobot having resigned himself to his fate, and pushes him off the 'mine'...explaining to the shocked Grimlock that they didn't place any mines when they left, and the click had just been his crushing an old armor buffer that Ratchet had discarded. Strongarm finds Sideswipe coming to, informing him that everything is fine; he wonders why the scavengers didn't finish him off or take their prize.
Buzzstrike releases Paralon from his control, letting the Decepticon come around in bewilderment. Buzzstrike spins a tale to the somewhat angered scorpion about being surrounded by Autobots and thus having to run for it, without there being time to recover the plasma rifle. Paralon grudgingly accepts this, but he warns Buzzstrike not to say anything to "the others" about their failure, as he intends to be the greatest scavenger of all and it won't do to be laughed at. He pushes aside a false rock face to reveal the ramp of a Cybertronian scout-ship, which the two board, Buzzstrike still looking not quite convinced of their virtues. Regrouping outside the base's ruins, Bumblebee compliments Sideswipe on his initiative; Sideswipe admits that knowing about history might have been helpful after all. Bee calls up Fixit - the interference having cleared - and gets the word that they are all-clear of Decepticon signals. Sideswipe then observes that he had grabbed an artifact on his way out, that he produces; Bumblebee panics at seeing the small disc, insisting it be handed over, but Sideswipe activates it - revealing it to be Bumblebee's old holodiary, showing the Autobot scout in legwarmers as he tried to make the Cybertronian equivalent of an exercise video. The team cracking up as Bee stammers for an explanation and then grabs for the device, the two Autobots scuffling and then transforming into car form to chase each other as the others resume laughing.
"Yeah, history. When everything was slow. Like Strongarm!"
-Strongarm punches him-
"How's that for 'slow', punk?!"
- —Sideswipe and Strongarm engage in some team bonding.
"This tour stop is special, team. I think you're really gonna get a kick out of this."
"We get to kick something?"
"No, we just... alright, just c'mon."
- —Bumblebee gives Grimlock the wrong idea.
"Grimlock, if anyone asks, you're...a big green metal robot from outer space that can turn into a dinosaur."
"Gotcha! ...hope I can remember that."
- —Bumblebee makes sure Grimlock remembers his cover story.
"This map better be right. I don't want to be wasting my time."
"Considering what you did to that Decepticon to force him to give you that map, I doubt he played any tricks on you."
- —Paralon and Buzzstrike discuss how the customer is always right.
"You may have stepped on a mine, maybe another of these old defense mechanisms. If you take your foot off it, it could..."
"The next word out of your mouth better be 'tickle'!"
- —Strongarm and Grimlock are in a bit of a predicament.
"Most undignified...but highly amusing."
- —Even Drift has a sense of humor.
- The Autobots' former base is, of course, their old headquarters from Transformers: Prime, which was destroyed in the season two finale "Darkest Hour". The military base the team arrives in is implied to be Hangar E, their replacement headquarters from season three.
- Bumblebee's reminiscing is full of callbacks to Prime:
- Bumblebee's comment that his workout video was "in style" at the time of its recording implies that the Autobots were on Earth in the 1980s. This is further supported by the visit to Mount St. Hilary in the next episode, as well as several comments made by the Autobots in Transformers: Prime.
- The Alchemor returned to Cybertron with all captured Decepticons aboard (bar one), implied to constitute the majority, if not totality, of escapees. While some remaining stragglers would later be shown to remain on Earth, at this point, the Autobots speak as if Decepticons in general are not a concern for the planet any more.
- The armor buffer Grimlock stepped on uses the same model that Knock Out commonly used.
- The sequence where Bumblebee and his team travel to Autobot Outpost Omega One bears a resemblance to the Transformers: Prime title sequence.
- Bumblebee notes that Buzzstrike was "powering up his host to some degree." The concept of Mini-Cons powering up their partners was the primary plot point of Transformers: Armada.
- Bumblebee scans a green jeep yet ends up with tan desert camouflage.
- If the hangar the Autobots GroundBridge into is Hangar E, this presents a small continuity snuffle, as it is shown to be right outside of the destroyed Outpost Omega One... while in Prime, the two bases were never shown to be this close, as the entire point of relocating to the hangar was to get AWAY from the original base.
- Bumblebee recalls the Decepticons invading the Autobots base, during which he fought two on its lower levels. This, of course, could never have happened during the timeframe we saw in the Prime cartoon, as the Decepticons are shown to have no knowledge of the location of the Autobot base, and promptly destroyed it with an aerial bombardment once they did. Either Bumblebee is telling a fib, or some Decepticons did get in at some point we never saw... and never came out again.
- Bumblebee is shown in his Robots in Disguise model in his workout video when he should logically have his Prime appearance, but we can't call this an actual error, as Rescue Bots has long established that continuity of visual appearance between series is not relevant to "Aligned" cartoon shows.