The amount of salt with which this rumor should be taken is enough to kill several slugs and put three old men on high blood pressure medication. That said, the source isn’t complete crap, so we’ll let you decide.
The website, Unleashthefanboy.com is claiming to have the script, which Michael Bay has already stated takes place four years after the third (turd) film. In it, the big bad of the film is none other than Unicron.
Here’s the basic outline of the film according to the site:
The opening of the film starts out with a meteor storm, which shouldn’t come as a surprise to anyone who’ve seen the last 3 movies. Cut to the scene where a mysterious metal space ball lands towards Stonehenge. Oddly enough the the ball is a spaceship. Vector Prime is the creator of the ship and is known for being the life long guardian of Primus. Which is the only one who can stop the deadly Unicron.
Optimus and the rest of the Autobots team up with Vector Prime to find the location of Primus, leading into Unicron’s lethal scheme. Along with GALVATRON, Unicron ambushes a secret Government base located in Colorado. This is very important for two reasons: The Decepticon Corpses are there and it’s has a great selection of new Cybertronian- Earth weapons and armor.
To make matters worse, Galvatron ends up demolishing the embassy to end up taking the lifeless Decepticon bodies and downloading their memories, which leads up to making Galvatron possessed by no other than Megatron. Somehow a human character named, Josie, ends up performing some weird surgery on herself that transforms her into some sort of cyborg. Those are the main parts of the story, but there are stand out points.
There seems to be some time travel elements involved, mainly between Optimus and Vector Prime. DINOBOTS are stated to make an appearance during a climatic battle. By the end Unicron finally puts his mark on Earth, transforming it into a mechanical sphere.