It is the year 2005. Unicron, a planet sized being, attacks and destroys a world called Lithone. Meanwhile, the Decepticons now occupy Cybertron. The Autobots occupy two Moonbases, and plan to take back Cybertron. Optimus Prime orders Ironhide and some other Autobots to go to Autobot City on Earth via a shuttle. Ironhide's group are attacked and killed by the Decepticons, who intend to use the shuttle to land in Autobot City, and then destroy it. As they arrive on Earth, Spike's son Daniel points out there is a hole in the shuttle. A massive battle begins between the Autobots and Decepticons.

Optimus Prime and some other Autobots head to Earth, having picked up a distress call sent out by Blaster. Optimus gets into a fight with Megatron, and defeats him. But before he can finish him off, Hot Rod intervenes, resulting in Optimus getting fatally shot.

Optimus still has enough power to hit Megatron one last time, badly damaging him. Starscream orders the Decepticons to retreat, and they leave Autobot City in Astrotrain. A dying Optimus reveals the Autobot Matrix of Leadership, which he passes over to his friend and new Autobot leader, Ultra Magnus. He explains that one day, an Autobot shall rise from their ranks, and use the power of the Matrix to light their darkest hour. Telling the Autobots 'till all are one, Optimus then dies.

The Decepticons dump several of their injured out of Astrotrain, including Megatron. Megatron is found by Unicron, who has a proposition: destroy the Autobot Matrix. He will rebuild him and give him new troops to command, but will belong to him now. Megatron initially refuses, but after Unicron threatens to destroy him, he changes his mind. Megatron is reformatted into Galvatron, whilst the other injured Decepticons are changed into Scourge, the Sweeps and Cyclonus.

The reformatted Decepticons return to Cybertron, where Starscream is being crowned as the new Decepticon leader. His reign lasts mere seconds, as Galvatron transforms into his cannon mode and destroys him with a single blast. Unicron then attacks Moonbase 1, as Jazz and Cliffjumper send out a distress call to Earth. They try to escape, but their ship is sucked back into Unicron. Bumblebee and Spike set Moonbase 2 to self destruct, but this fails to do any damage to Unicron at all, and their ship is also sucked into him.

On Earth, Ultra Magnus believes the Matrix may be able to stop Unicron, but the Decepticons then attack them. Some of the Autobots get onto two shuttles, which take off and head into space. The Decepticons follow them, shooting down the shuttle that Hot Rod, Kup and the Dinobots are on. Their shuttle crash lands on a strange world. On the other shuttle, Ultra Magnus orders for an emergency separation, making the front part of the shuttle detach from the rest of the ship. The Decepticons destroy the back part of the shuttle, believing that they've destroyed the Autobots.

The front part of the shuttle crashes onto the Planet of Junk, where the Autobots begin to make repairs. Meanwhile, Hot Rod and Kup have survived the crash, but have lost the Dinobots. They try to befriend some transforming robots they come across, only to be attacked by them. They are imprisoned, and meet Kranix, a survivor of Lithone. Kranix tells them about the vile beings who populate this planet: the Quintessons. He also warns them about Unicron, who destroyed his planet. The Quintessons then take Kranix away and execute him.

The Dinobots have also survived, but don't know where to go. An Autobot called Wheelie finds them, who speaks in rhyme and offers to help them out. Meanwhile, Unicron has told Galvatron about the surviving Autobots on the Planet of Junk, so the Decepticons head there. Ultra Magnus gets the other Autobots to hide, and attempts to use the power of the Matrix against the Decepticons. But he isn't able to open the Matrix, and after refusing to give it to Galvatron, he is destroyed by the Sweeps. Galvatron takes the Matrix, and intends to make Unicron his slave with it.

Hot Rod and Kup are sentenced to be executed by the Sharkticons, but start fighting back against them. Wheelie and the Dinobots then show up, and after easily besting the Sharkticons, the Quintessons still demand the Sharkticons execute the Autobots. Grimlock suggests the Sharkticons execute the Quintessons instead. The Sharkticons turn on their masters, leaving the Autobots free to take a Quintesson ship and leave the planet. Back on the Planet of Junk, the Autobots mourn Ultra Magnus, but are then attacked by the residents of this world: the Junkions, and their leader, Wreck-Gar.

The fighting stops when Hot Rod's group arrive, and are able to befriend the Junkions by using the universal greeting. The Junkions repair Ultra Magnus, bringing him back to life. He reveals that Galvatron has the Matrix, and Wreck-Gar says Galvatron has gone to where Unicron is. The Autobots and Junkions blast off in two ships.

Galvatron attempts to use the Matrix against Unicron, but is unable to open it. Unicron reveals he is a Transformer, and transforms into his colossal robot mode. He decides to destroy Cybertron, and begins to attack it. The Decepticons fight back, but Unicron swallows Galvatron, just as the Autobots and Junkions arrive. Hot Rod's group smash the Quintesson ship through one of Unicron's eyes.

The Autobots fall out of the ship, and Hot Rod finds Galvatron. Galvatron tries to ally himself with Hot Rod, but Unicron threatens to obliterate him if he doesn't destroy Hot Rod. Elsewhere, the other Autobots and Daniel come under attack from Unicron's internal defenses, and some stray shots cause lots of water to be released, separating Daniel from the others. He finds his father, along with Bumblebee, Jazz and Cliffjumper, are about to be dropped into an acid vat, but he's able to save them all just in time.

Galvatron is about to tear Hot Rod's head off, but Hot Rod grabs the Matrix, which glows brightly. He kicks Galvatron off and is changed by the power of the Matrix. Hot Rod hears the voice of Optimus Prime, who tells him to arise as Rodimus Prime. Galvatron tries to stop Rodimus, but Rodimus picks him up and throws him with such force that he crashes out of Unicron, and is sent tumbling through space.

The energy from the Matrix courses through Unicron, ripping him apart. Rodimus regroups with the other Autobots, and then drive out of Unicron's eye. Unicron yells that they cannot destroy his destiny, but his head then bursts off, and his body explodes. The Autobots and Junkions land on Cybertron, as Rodimus says this will mark the end of the Cybertronian wars, as they march forward to a new age of peace and happiness -'till all are one!

Notes

-The movie is considerably darker than the TV series, as within the first few minutes there is a scene which features planetary genocide. There is then, of course, the biggest difference between the movie and the TV series: characters dying. For the movie -and for the movie only -the Decepticons outright kill several Autobots. In the series, characters would get injured all the time, but they'd always get repaired and pull through. Not the case here, however.

-The reason for this is because of the situation with the toys. The 1984 and 85 toys were mostly being pulled from store shelves, replaced with the new 1986 lineup. When faced with what to do with the old characters, the writers came up with an idea: kill some of them off. Hasbro, not caring about old product, were fine with allowing this to happen. Kids would surely be fine with watching their toy collections getting wiped out on screen, and having to buy the new toys... right? Not quite. This movie bombed at the box office and put the Transformers brand into a downwards spiral, one that it wouldn't truly recover from until 10 years later, when Beast Wars was released.

-During Unicron's attack on Lithone, during this shot, there are several backgrounds featuring ruined buildings, seen on the left. They appear to be backgrounds from Fist of the North Star, a series animated by the same company who animated this movie: Toei.

-In an earlier draft of the script, Autobot City is the place where the Autobots create energon cubes, hence why Ironhide is sent there by Prime to collect cubes, and why Megatron wants to destroy it. Unfortunately this bit of info was cut from the final script.

-Speaking of which, it seems the Autobots now also use energon cubes -previously in the TV series, only the Decepticons were using these.

-One of the new Autobots is Arcee. Writer Ron Friedman has said in an interview that the idea of including a female Autobot as a permanent member of the main cast was met with heavy resistance by Hasbro. Ron wanted to include Arcee as his daughter was a fan of the TV series. Unfortunately, no Arcee toy was produced, despite a prototype being made.

-The script refers to the Dinobots as "the four Dinobots" at one point, which hints that the writers made an error about how many characters were in the team. Snarl, who transforms into a Stegosaurus, makes a couple of brief, non-speaking cameos in the film -such as when the Quintesson ship lands on the Planet of Junk -but is otherwise absent for the most part. It just seems this was an error, as the entire team appears together in several episodes of the third Transformers series.

-The death of Optimus Prime is one of the most memorable and controversial moments of The Transformers. Prime's death was met with massive backlash from upset kids, much to Hasbro's surprise. The backlash was so great that Hasbro had to bring the character back to life in the next season of the TV show.

-Initially two Cyclonus characters are created. Unicron states "Cyclonus, the warrior, and his armada". But one shot later, only one Cyclonus is seen, and it stays that way for the rest of the movie. It is believed that, like how Scourge has the Sweeps following him around, Cyclonus would have some identical clones doing the same thing. But the concept was dropped from the movie. A couple of episodes of the TV show's third season do feature Cyclonus clones flying around in battle scenes, but the concept was dropped there too.

-During the coronation scene, Skywarp, Thundercracker and the Insecticons can be seen watching, despite them being reformatted into new characters in the previous scene. The storyboards or script don't call for these characters to be there, so it appears the animators threw them in there in error.

-In an earlier draft of the script, Unicron does not immediately attack the second Moonbase, after destroying the first. He was supposed to attack it after the scene where Wheelie shows the Autobots the Quintesson ship. It seems this was a late change, as it creates a continuity error -during this shot, Moonbase 2 can clearly be seen, despite being destroyed by Unicron moments ago.

-The auto-combatant is not named in the movie, but that's what it's called in the script. Despite having a line of dialogue, it's not featured in the credits. It was voiced by Frank Welker.

-The Quintessons are introduced in this movie. They were originally meant to have bigger roles in earlier versions, such as being inhabitants/operators of Unicron. In the finalized version of the film they just appear to be a bad species who kill others for fun, but the third season of the TV show expands their role quite a bit.

-Kup claiming that Hot Rod "left a piece out" when he fixed him was originally meant to pay off later, during the scene where the two are dumped into the Sharkticon pool. In an earlier script, Kup realizes that the missing piece has made him double jointed, and he is able to remove his restraint, and then shoots Hot Rod's off. The finalized film changed this so the restraints simply vanish as the two Autobots fall.

-Ramjet, Thrust and Dirge are all seen being destroyed by Unicron. However, all three of these characters will appear in the third season of the TV series, and have speaking roles. Their toys were still available in the 1986 lineup, so it seems their "deaths" in the movie were a mistake.

-The purple Decepticon ship Unicron gives to Galvatron is also seen being destroyed during the final battle, but it actually reappears again in the top left corner of this shot, and will appear in the third season of the TV series.

-During the credits, Walker Edmiston is credited with voicing Inferno. Inferno does not appear in the movie at all. Walker did record a line for Inferno, but it was not used in the film -see the dialogue script differences for more info.

-Don Messick is also credited with voicing Gears. Gears makes a cameo near the start of the film, but does not speak. Again, like with the above, Don did record a line for Gears, but it wasn't used. For some reason Don is not credited for voicing Scavenger, who does speak in the movie.

-The storyboard and dialogue scripts mentioned below feature many scenes and shots that were cut. Fans question whether or not any of these scenes were animated, and if they were, if they'll ever be released. As of 2025, only one deleted sequence has been found:

When Astrotrain takes off from Autobot City, it fades out. But this deleted footage shows that originally, it would have zoomed into the top left of the shot, showing some Autobots gathering around the fallen Optimus Prime. This was storyboarded like this, and the fact that this footage exist has led some fans to believe there could be more cut stuff waiting to be found.

Early scripts

Several early scripts for the film have been made available to all, which have numerous differences in them compared to what's seen in the finished movie. You can read about some of them here. Differences include unused characters and altered scenes.

Promotional trailer

This promotional video was created to sell the movie to investors. It contains several scenes, some of which made it into the finished film (with a few differences), but several of the scenes are exclusive to this trailer. Read about the trailer here.

Storyboard differences

This section looks at the film's storyboards, which contain numerous differences. There were several scenes storyboarded which never made it into the finished film, and many storyboarded shots were also cut. The storyboards reveal the fate of several Autobots, who had their appearances cut in the end.

Dialogue script

The film's dialogue script contains all of the dialogue that was recorded for the movie. It has many lines for scenes that were cut from the finished film, whether or not any of these scenes were animated is currently unknown. You can read about them all here.

Voice cast

Character	Voice Actor
Arcee	Susan Blu
Astrotrain	Jack Angel
Blaster	Buster Jones
Blitzwing	Ed Gilbert
Blurr	John Moschitta
Bonecrusher	Neil Ross
Brawn	Corey Burton
Bumblebee	Dan Gilvezan
Cliffjumper	Casey Kasem
Cyclonus	Roger C. Carmel
Daniel	David Mendenhall
Devastator	Arthur Burghardt
Frenzy	Frank Welker
Galvatron	Leonard Nimoy
Grimlock	Gregg Berger
Hook	Neil Ross
Hot Rod/Rodimus Prime	Judd Nelson
Ironhide	Peter Cullen
Jazz	Scatman Crothers
Kranix	Norman Alden
Kup	Lionel Stander
Megatron	Frank Welker
Optimus Prime	Peter Cullen
Perceptor	Paul Eiding
Rumble	Frank Welker
Scavenger	Don Messick
Scourge	Stan Jones
Scrapper	Michael Bell
Shockwave	Corey Burton
Slag	Neil Ross
Soundwave	Frank Welker
Spike	Corey Burton
Springer	Neil Ross
Starscream	Chris Latta
Swoop	Michael Bell
Ultra Magnus	Robert Stack
Unicron	Orson Welles
Wheelie	Frank Welker
Wreck-Gar	Eric Idle