The Master Builders

Up in the sky Powerglide is talking to himself, prattling on about nothing important until Starscream and Skywarp arrive to shoot him down. Har har. The next thing we know we get to see Grapple working on a small model of a solar power tower - the model is ready and works but he needs Optimus Prime's permission to build the real thing. Hoist is with him though and says he will help present it. Meanwhile Spike is teaching Prime how to play basketball.
 

The two Autobot mechanics then arrive and show Prime the model and what the real thing can do. Prime is impressed with it and says the energy would be beneficial but declines giving permission for them to build a full size one as if Megatron and the Decepticons managed to get their hands on it the results could be devastating. Teletraan-1 then reports in stating that Powerglide has been shot down and needs assistance, so Prime sends Grapple and Hoist out to his location. They soon get there and fix him up, and as soon as that is done the red jet with the big ego gives his thanks and is soon in the air again.
 

This leaves the other two Autobots to roll out back to home but in a canyon Grapple transforms and asks Hoist if he would consider helping him build his solar power tower anyway, even without Prime's permission. Hoist reminds him about what Optimus said and then goes on to say that the two of them couldn't build it by themselves, they'd need help. The Constructicons have been listening the whole time though and Scrapper jumps down to try and talk to them but is blasted out of the way.
 

The other Constructicons cause a landslide which traps the pair and Scrapper resumes talking. He tells them that the Constructicons have now left Megatron as he took advantage of them and they want to help Grapple build his solar tower. What either side doesn't know is that Megatron and Starscream are secretly watching the entire meeting via a hidden camera in a rock.
 

Hoist doesn't want to team up with Decepticons but Grapple does just so he can build his machine. But before the partnership can begin he demands proof of their loyalty. Scrapper says they will get it and head back to the Decepticon base, where they are immediately cornered by the other Decepticons. Megatron starts to play the tape he recorded of the earlier meeting but the Constructicons explain that they are still loyal to Megatron and want to build the tower just so they can steal it for creating energy for the Decepticons.
 

After hearing of this plan Megatron agrees to it and gives the Constructicons the proof they need to show the Autobots. A little later on, the Constructicons return to Grapple and Hoist and reveal what they have: energon. Scrapper claims that they stole this from Megatron and both of the Autobots are chuffed as they can use it to construct the tower.
 

The Constructicons then go off to get building materials, although they do it without the Autobots seeing them as they probably wouldn't like their methods: stealing. They bring the stuff back and soon the Autobot/Constructicon alliance begins, with the solar power tower quickly being worked on.
 

Optimus and some of the other Autobots are now playing basketball outside when Prime calls for a time out. They then find out that they haven't heard from Grapple for a while and Spike says he saw him and Hoist leave a few hours a go and haven't seen them since. Prime says he'll have Powerglide fly out to try and locate where they are. Meanwhile the power tower is nearly finished as the Autobots and Constructicons add the finishing touches.
 

Powerglide soon finds where they are and sends Teletraan-1 a direct video feed showing the two Autobots with the Constructicons. Prime doesn't know why they are working together but senses trouble and gets together a group of Autobots to go and find out. Meanwhile Devastator helps Grapple put the final piece of the tower in, making the machine complete. As Hoist and Grapple marvel at their invention they are suddenly shot from behind and land in a pit.
 

Megatron then appears and tells them that they will die in their own tower, and Devastator places them inside it. Later on the Constructicons are busy making many energon cubes when the Autobots arrive and see that the tower has been finished but there are no signs of Grapple of Hoist. The only way to find them is to attack so Prime leads an attack on the tower.
 

Warpath immediately starts to make a mess of the place and sends the Constructicons running off to hide. Megatron tells them to merge into Devastator and after doing that the gestalt easily beats off most of the Autobots. Powerglide then attacks from the skies but Ramjet attempts to stop him only to be accidentally slapped to the ground by his supposed friend.
 

Since they can't beat Devastator with lasers Prime tells Smokescreen to go around behind him and then make his presence known. When Devastator sees him he attempts to kick the Autobot but he gets away. Devastator's kick instead hits the tower and before he can move away from it the Autobots concentrate their fire on his back.
 

This sends him crashing through the tower, destroying it completely. Megatron sees that it is nothing more than a pile of junk now and after promising that the Autobots will pay for this, he retreats and the beaten Constructicons follow. Prime then orders the Autobots to clear away the wreckage as Grapple and Hoist must be somewhere in it.
 

The Autobots are still at it well into the evening when Brawn finds something and smashes it open, revealing the two missing Autobots. After accepting their apologies Prime tells them that they must head back to base for repairs but then return here to clear up the rest of the wreckage by themselves.
 

As most of the Autobots move out back to base, Grapple finds that small model he showed Prime earlier and Hoist tells him that there will be more towers for him to build in the future. After agreeing that this solar tower was magnificent for the while it lasted both of the Autobots transform and roll for home.

When the Constructicons first arrive back at base, several of the Decepticon jets are armed with guns rather than pointing their arm cannons, which is a rarity.

The original title of this episode is "The Master Builders" but on several DVD releases, for whatever reason, the episode is called "The Master Builder".