One day the Combaticons thought it would be fun to to visit a city. Onslaught tells everyone to transform and they do and they all somehow manage to go down a street together. Even the two that are meant to be able to fly in vehicle mode decide to use the road.
Onslaught then tells everyone to combine into Bruticus for some reason, making his previous order rather redundant. Anyway the team unite into their large robot form, but after taking a few steps forward he looks up only to be hit square in the chest by a laser beam which causes him to explode! The shot was fired by Defensor - the combined form of the Protectobots. This new robot proves to be a jerk as he doesn't bother to help clean up Bruticus' remains and just leaves instead.
Swindle has survived however and starts looking for spare parts to help rebuild his friends, so he goes to some evil army general to do some trading rather than doing the normal thing and taking them to the Constructicons (maybe they were still bitter about losing to Bruticus here). Meanwhile at the Decepticon base, Megatron has a simulation running of his latest plan: to move the moon out of the Earth's orbit and then control the tides because that will so obviously be the key to all of their energon problems.
Well, Megatron does at least go on to add that Soundwave has made some new device that will help them flood a canyon to create a "nearly limitless power". Meanwhile in bizarre plot twist #1 Swindle is now actually selling the parts of his friends rather than trying to rebuild them, and has had lucky selling their weapons and computer systems. The general isn't interested in the other parts though and kicks Brawl's head away.
Later on Skywarp goes off to the Combaticon base and tries to communicate with them but does not receive a response. He transforms and lands to find the base devoid of any life at all but he does find some parts and recognises them to be parts of certain Combaticons. Seeing a trail of these parts leading outside the base, Megatron tells him to follow the trail.
Swindle has gone to a junkyard just so he can dump the useless parts of the other Combaticons but as he gets rid of them, Skywarp and Starscream arrive and they see that the rogue Combaticon is up to something. So Starscream captures him and then they all head back to the Decepticon base.
Swindle says that what happened wasn't his fault but Megatron wants Bruticus put back together again and tells Swindle to get to it - and just to make sure he doesn't take his time, Soundwave puts a time bomb in his head which will go off in 15 hours, and the only way the Decepticons will remove it is when the Combaticons are all online again. With this new task ahead of him Swindle goes back to the places where he sold parts and reclaims them - without asking, of course.
Some time later all of the Combaticons have been re-built, so Megatron tells the team to transform into Bruticus. Most of the group start to move but for some reason Brawl remains still - Swindle has to guide him over to the rest of the team. Starscream thinks that something is wrong.
The Combaticons attempt to merge but fail miserably and all fall down. Swindle then reveals that the reason they can't combine is because Brawl is missing his personality chip -he couldn't find it but he didn't think it would matter. Megatron tells him to think about this: the bomb is still in his head and will still go off unless he finds the chip pretty quickly.
Meanwhile at Benjamin Franklin Pierce High School, Mr. Robinson is going to give his class a demonstration in how a laser beam works. Despite concern from the class about how lasers are meant to be dangerous, Mr. Robinson says that this laser is far too low powered to be a threat but as he turns it on in destroys the piece of metal meant to block it, burns through several books and then smashes a window. Two jerks called Martin (orange shirt) and Roland (white shirt) are the ones responsible, but they think that the event is hilarious, despite the fact that someone could have been killed.
The teacher doesn't understand why the laser destroyed things but then hears the laughter and instead of having the two boys expelled on the spot he has a far worse punishment: they have to get the blue ribbon at the science fair or he will fail them both. And they have to work with Elsie Presser, which they really aren't happy worth and when they meet her later they tell her where to go.
However this negative talk soon ends when they see a building on fire and some people trapped near the top. But the Protectobots appear and save the day by helping the fire crews to put out the fire whilst also saving the two people.
After seeing the Protectobots in action, the kids come up with a terrible/brilliant idea: to build their own robot! But with parts being so expensive the only place they can go to get some is the local junkyard, where they gather as many bits and pieces together as possible and then take them back to the school. They start to work throughout the night in the hope of completing their new creation so they can pass the science course. Martin even comes up with a name for their robot: Biotronic Operational Telecommunicator - or B.O.T. for short.
The kids get B.O.T. together and turn his power on but he doesn't seem to work properly. Elise says that she is getting some strange readings from some chip she found and decides to try installing that inside B.O.T.'s head, but when she puts in in B.O.T. becomes angry and starts to trash the room!
As B.O.T. continues on his rampage the kids decide that they need to try and shut him down but they've go no idea how -Elise tries talking to it but Martin has a much better idea and grabs the laser that was used earlier to send B.O.T. running off. With their creation gone for now the kids then decide that they can't deal with this problem by themselves but they know who can: the Protectobots! So they use one of the school's computers to send out a distress signal.
Teletraan-1 picks up the signal and Gears reports it to Optimus Prime. Prime tells Gears to go to the source of the
S.O.S to check it out and for Bumblebee and Ironhide with him. Meanwhile Swindle is busy harassing the junkyard owner about where the parts are he dumped here earlier as he still can't find Brawl's personality chip.
Gears, Ironhide and Bumblebee arrive at the school and meet the kids, who are disappointed that they aren't the Protectobots but since they are all on the same side they soon get over this. B.O.T. is seen running towards a run-down building so the group go after him, and despite Ironhide telling the kids not to follow them they do anyway and use a lift inside the building to move up to the top floor to hopefully find B.O.T.. Meanwhile the Autobots take the stairs believing they are chasing B.O.T. but...
...it turns out to be Swindle at the top, who has seen what was going on and blasts the Autobot group whilst taking something from B.O.T., since he has realised that Brawl's personality component has been put inside this new robot. The kids get out of the lift without finding B.O.T. so they and the Autobots run outside only to see Swindle making his getaway before they can do anything about it. The kids don't recognise who the yellow and purple robot was but the Autobots sure do.
Back at the Decepticon base Brawl is finally in his own body again and Megatron warns Swindle that if he ever does something like this again he will have him melted down. The Combaticons then transform into Bruticus correctly as Megatron says that they will soon control the Earth's oceans.
Later on the kids have B.O.T. taken back to the school where they find that the thing Elise had put in it earlier has gone -whatever it was, it must have been Combaticon property. But Martin prints off a brain-wave chart and says they can home in on this signal to find where this missing component is now, and they go off to look for it because some people just don't know when to stop. But they then are forced to stop when the signal seems to be pointing straight out to the sea.
Obviously the kids can't go out to the sea but Elise then gets some wacky idea to do something that makes it possible for them to listen in to the signal, and her plan works as they soon hear the Decepticons talking and Megatron's latest idea: instead of using their new weapon on the moon straight away they decide to test it on the Autobot H.Q. first. The kids head back to the Autobots and tell them of Megatron's plan.
The Decepticons are all ready outside the Autobot base when Optimus appears with a group of Autobots and the Protectobots also arrive to help in the battle. As the two sides fight it out, the kids are still inside the base and are worried about the Decepticon weapon pointing straight towards them. They want to help the Autobots since they helped them earlier and to do this they send B.O.T. out to the battlefield.
The Protectobots merge into Defensor, who activates his forcefield...but the Decepticons just stand there and wait for it to run out of power and then shoot the gestalt, sending him back to the standalone Protectobots. Brilliant plan there guys.
Bruticus then tries to use the disrupter weapon on the Autobot base but it starts to fire wildly by itself and is soon sending several Decepticons flying. Turns out that B.O.T. was the one responsible for this as he was messing about with the controls, and after pressing the "OVERLOAD" button, the weapon explodes and so takes B.O.T. along with it.
Optimus Prime thanks the kids for helping them in the battle but Elise says that they couldn't have done it without using Teletraan-1 to control B.O.T.. As they now don't have a robot anymore she starts to ask if the Autobots have any spare parts available for them to build a new one but Martin and Roland gag her and then take her out of the base as that "about wraps it up" - Martin's words, not mine.
This episode seems to be viewed as the worst one of the lot for seasons 1-4 of Transformers. See here for more info on that.
Instead of using newer characters like the Protectobots more prominently, several older characters are used like Ironhide, most likely in one last effort to plug the toys before the upcoming massacre.
This is the first and last time we see the Combaticon's base.