The heroic character Optimus Prime appears in the original trilogy Micheal Bay hasbro live action Transformers films Transformers (2007) , Transformers: Revenge of the Fallen (2009) , and Transformers: Dark of the Moon (2011) as the leader of the Autobots and one of the main protagonists of the first three Michael Bay Transformers films. In these movies, Optimus Prime is able to transform into a conventional Peterbilt 379 cab, rather than the cab over design of his original Generation 1 body. In Transformers: Dark of the Moon, he regains his first generation trailer. Also straying from the classic G1 design, Prime's vehicle mode is now decorated with red flames painted onto a blue body à la Rodimus Prime, his Generation 1 successor. The reason for the major change was due to Director Michael Bay's decree that mass displacement does not occur when they transform, requiring Optimus's vehicle form to have more mass to achieve the desired size in his robot form. The heroic autobot talking truck's voice was provided by Peter Cullen who also first voiced K.A.R.R Knight Automated Roving Robot in the Original Knight Rider Series in his first villainous debut appearance in Season 1 of The Original Knight Rider Series and also the short-lived revived Knight Rider series continuation 2008-2009 in Season 1 as K.A.R.R 2.0 where he reprises his vocal role as the voice of K.A.R.R in Knight Rider and as well as also was The original first voice of Optimus Prime in the original The Transformers Generation one cartoon (1984-1987). and as well as also The Transformers: The Movie (1986). as the heroic character and autobot leader Optimus Prime and as well as Nemesis Prime In Transformers: Prime (2010-2013). as well as Transformers: The Last Knight. (2017).
Although the heroic autobot character was redesigned to some extent, like the other characters in the film, many classic design elements still remain in his robot mode including a predominantly red torso, primarily blue legs, the presence of windows in his chest, smoke stacks on his shoulders, and a head design influenced by the original Optimus Prime, featuring the iconic faceplate and ear finials. The faceplate is now able to retract to reveal a mouth. His weapons include his iconic ion blaster stored in the form of the fuel tanks on his back, and a shell cannon stored on his back, two retractable energon blades that extend from both forearms, which is a homage to Prime's energy axe in the Generation 1 hasbro animated series, two retractable energon hooks on both of his forearms, and bladed knuckles. The trailer contains an energy axe, a shield, and flight gear. In the later IDW comics, he displays the ability to produce a holographic driver.