Released to Unleash the Fanboy, a script purporting to be the most recent draft of Michael Bay's upcoming Transformers 4--120 pages of potential spoilers. Here's how the site describes the nature of the find:
"I can’t give you any specifics about our source, fearing that he may lose his job, but he works in a “secure document disposal” firm, and it just so happened that a copy of the latest Bayformers script (revised on 11/30/2012) came across his path. After some hours of research, we think this is a legitimate copy (thought we can’t be certain), so we’re really stoked to share it with you… but don’t kill us if we’re wrong."
UTF claims that the script features Unicron as its central antagonists, with characters like Galvatron replacing Megatron as the leader of the Transformers and Primus, the "Unicron killer" joining the Autobots' cause. They also claim the Dinobots will appear.
Below are the bullet points, as given by UTF, which explains that the film begins with Galvatron becoming possessed by Megatron after downloading his memories from his corpse, and that in the course of the corpse-theft, a human named Josie gets injured and ultimately turned into a cyborg called Circuit Breaker:
- Optimus, Vector Prime, and a handful of Autobouts travel to Mount St. Hellen on the day of its eruption in order to retrieve Primus from Space & Time… or at least I think that’s what they’ve done. Galvatron/Megatron attacks them, revealing himself to Optimus, and craziness unfolds
- They return to the present in order to defend the portal at Stonehenge against Megatron and his Unicron flunkies, in an attempt to survive long enough to ensure Primus’s return
- Josie/Circuit Breaker goes on a wild binge of Transformer murders, unable to distinguish between Autobots and Decepticons because she’s so damn pissed off, having almost been killed.
- Eventually Josie joins forces with the Autobots.
- As the climatic battle unfolds, with Unicron drawing closer to Earth, a group of Dinobots jump through the portal to assist Optimus. Yeah, I said it… DINOBOTS!
- Unicron arrives, transforming the planet into a mechanical sphere reminscent of Cybertron, but he never gets a chance to finish.
- Primus finally makes his debut. He defeats Unicron, kicks that baddie’s soul out of his gigantic metal body, and creates a new planet out of the corpse, perfectly fit for the Autobots.
- In the midst of Unicron’s defeat, Optimus kills Megatron/Galvatron, and all ends well. Kinda. The closing shot reveals Galvatron’s secluded ship, hovering in space, with two bright red eyes shining from within. DUN DUN DUN!
On the other hand, it's the first new chapter following the first trilogy, with new human leads confirmed and Megatron ostensibly gone. And given the popularity of Transformers: The Movie among fans, which saw the Dinobots join the fight against Galvatron and Unicron, it's not beyond the realm of possibility that as Bay's last move he would want to put some of those characters and concepts into use, giving the hardcore fans something to be excited about.