New leaks regarding the fifth installment to the hugely successful Transformers franchise "The Last Knight" will feature new spoilers and the addition of a new character in the upcoming sequel.

Latest details churned out from rumor mills purportedly involve Optimus Prime and his Autobots crew in the unfolding of events leading to the uncovering of truth that explains the Transformers' origins on planet Earth.

As reported by JoBlo, the plot in "The Last Knight" will feature Optimus Prime's quest to rehabilitate his home planet Cybertron which has since become a desolate and inhabitable world as a result of the disastrous civil war between the Autobots and the Decepticons. The leaked storyline also revealed that the Autobots leader is also partially responsible for Cybertron's destruction. He tries to make amends for his action by searching for a mysterious artifact somewhere on earth that will supposedly help to nourish his native home back to life.

As reported by Games Radar, the artifact that Optimus Prime was keen on retrieving has something to do with medieval wizard Merlin whose magical power reportedly came from a Transformer who were scattered across the world since time immemorial following their escape from Cybertron during the Autobots-Decepticons civil war.

While details surrounding the artifact remains unknown, rumors suggest that the mysterious item may have King Arthur's legendary sword known as the "Excalibur" which could partly explain the idea behind the sequel's title.

The movie will see Mark Wahlberg (Cade Yaeger) and Josh Duhamel (Lt. Col William Lennox) reprising their roles. The plot also revealed the return of Bumblebee, Drift, Crosshairs, Hound and the Dinobots from "Age of Extinction" sequel. From the Decepticons side, Megatron/Galvatron and Barricade will return to the big screen again in their villainous quest to harm the earth.

Apart from the returning characters, there will also be a bunch of new Transformers characters that include Cogman (an Astin Martin) and Squeakes (a Vespa). Another important from the reported leaks include the addition of "Hannibal" movie star Anthony Hopkins in his role as the Transformers' "Creator," Yibada reported.

The movie is directed by Michael Bay which is expected to hit the theaters on June 23, 2007.