The film takes place two years after the end of the first part. The Autobots, meanwhile, have allied with the humans, including Lennox and Epps, and now work together in a secret task force called NEST, which reports to the U.S. Armed Forces High Command but also involves soldiers from other countries. Officially, the U.S. Government continues to keep the existence of the Transformers a secret. At the beginning of the movie, NEST tracks down and destroys the two Decepticons Demolishor and Sideways in Shanghai. Shortly before he is killed by Optimus Prime, Demolishor gives the cryptic hint that "The Fallen" will rise again.
Meanwhile, Sam Witwicky prepares for his move to the college campus. Since he's not allowed to own a car as a freshman, he has to leave Bumblebee in his parents' garage, and he also has to leave behind his girlfriend Mikaela, who can't afford college and instead works in her father's garage, who was recently released from prison. However, while preparing for the move, Sam finds a shard of the Allspark cube that turns all the kitchen equipment into little robots, whereupon the overzealous Bumblebee, while eliminating the robots, also destroys part of the house at once. After touching the shard, Sam begins to see mysterious symbols. Arriving at college, he meets his roommate, Leo Spitz, who runs a conspiracy website and is convinced of the existence of the Transformers. At a party, Sam also meets his fellow student Alice, who immediately tries to seduce him.
Meanwhile, NEST gets a visit from U.S. Security adviser Theodore Galloway. The latter is convinced that the new Decepticons have only come to Earth because the Autobots are still there. He therefore urges them to leave Earth. Shortly thereafter, the Decepticon Soundwave, disguised as a satellite in Earth orbit, sends his minion Ravage to the NEST base on Diego Garcia, where he steals another shard of the Allspark Cube that Optimus Prime took at the end of the first part. Ravage, some Constructicons and a Decepticon named "The Doctor" dive down into the Laurentian Trench, where Megatron's remains were buried at the end of the first movie, and bring him back to life with the help of the Shard. Megatron then goes to a Decepticon spaceship on one of Saturn's moons, where his second-in-command Starscream and his master The Fallen await him.
Meanwhile, a Decepticon named Wheelie attempts to steal the Allspark shard that Sam has left in the care of his friend Mikaela, but is discovered and captured by Mikaela in the process. Mikaela immediately sets off for Sam, whom she surprises, however, in an apparently embarrassing situation with Alice. Alice, however, turns out to be a Decepticon; on the run, Sam, Mikaela and Leo are captured by the Decepticons. Megatron instructs the "Doctor" to remove Sam's brain in order to get the information from the All Spark shard, but the Autobots have tracked them down and free Sam, Mikaela and Leo. On the run, however, Optimus Prime is confronted by Megatron and several other Decepticons and is killed in battle.
The Fallen then addresses the world in a televised speech and demands Sam's surrender. The latter hides with Mikaela, Leo, Bumblebee and the Autobot "twins" and eventually seeks help from Leo's rival "Robo-Warrior", who turns out to be former "Sector 7" agent Seymour Simmons. From this and the Decepticon Wheelie they finally get a clue to the meaning of the symbols in Sam's head. At the Smithsonian National Air and Space Museum, they discover the old Decepticon Jetfire, but he says he has switched sides and tells them about The Fallen. The latter belonged to the first "Primes", the ancestors of Optimus Primes, who had already been created in the year 17.000 v.Chr. Had come to Earth and set up a machine called a "harvester" there. The task of the latter was to destroy suns in order to create Energon, the energy source of the Transformers. The Primes, however, never intended to destroy the sun of an inhabited world. The Fallen, however, out of greed for power, betrayed his "brothers", who then sacrificed their lives to hide the "Matrix of Leadership", the key to activating the Harvester. The symbols in Sam's head now contain the clue to the hiding place of the Harvester as well as the Matrix.
Jetfire teleports himself as well as Sam, Mikaela, Leo, Simmons, Bumblebee and the "twins" to Egypt. Between the pyramids of Giza, they find the next clue and head to Jordan. There, in the rock city of Petra, they discover the tomb of the "Primes", the brothers of The Fallen, where Sam finds the Matrix. Since Jetfire says that only a Prime can stop The Fallen, Sam hopes to use the Matrix to bring Optimus Prime back to life, but it turns to dust in his hands. Sam takes the dust and together they make their way back to Egypt, where in the meantime the NEST team requested by Simmons is on its way, including the lifeless body of Optimus Prime.
On the way to the agreed meeting point, however, they are attacked by the Decepticons. The Constructicons connect to Devastator, who immediately starts tearing apart the Great Pyramid built around the Harvester. While the Autobots and NEST engage in a battle with the Decepticons, Megatron tries to trap Sam with the help of Sam's parents, whom he had captured in Paris, but Bumblebee manages to save them both. Shortly after, Sam is mortally wounded by a shot from Megatron, but as the dust of the Matrix spreads in his hand, he encounters the Primes in a vision, who let him know that he has been chosen to find the Matrix and secure the life of the last Prime. Sam comes back to life, and the dust in his hand turns back into the Matrix. With this, he actually manages to bring Optimus Prime back to life as well.
In the meantime, Simmons has requested assistance from a warship equipped with a railgun, which he uses to destroy Devastator. Thereupon The Fallen steals the Matrix. Activates with it the Harvester. Jetfire, who has since also entered the fray and suffered life-threatening injuries, unceremoniously snatches his "Spark" and instructs Optimus Prime to use the parts of his body to fight The Fallen. Ratchet and Jolt then equip Optimus Prime with a kind of "armor" made of Jetfire's parts, and with it Optimus Prime actually manages to destroy the Harvester and subsequently kill The Fallen. At the suggestion of Starscream, the badly wounded Megatron then takes flight.
In the final scene, the Autobots, NEST, Sam and his friends return to the U.S. On an aircraft carrier.
At the center of the plot, as in the first part, is the now 19-year-old college student Samuel James "Sam" Witwicky (Shia LaBeouf), who has befriended the Autobot Bumblebee in the course of the first part. This time Sam again becomes the target of the Decepticons when the knowledge of the destroyed Allspark Cube is accidentally transferred into his head.
Mikaela Banes (Megan Fox) became Sam's girlfriend over the course of the first installment. Unlike Sam, Mikaela cannot afford a college education. Therefore now works in her father's workshop.
Newly introduced is Leonardo Ponce de Léon "Leo" Spitz (Ramon Rodriguez), Sam's roommate and operator of the conspiracy website "The Real Effing Deal" (in the German version "Der hammerheiße Deal"), whose goal is to prove the existence of the Transformers. Sam's parents are Ron Witwicky (Kevin Dunn). Judy Witwicky (Julie White). At the end of the first part, they learned of the existence of the Transformers, but keep their knowledge secret at the request of the U.S. Government.
Captain William Lennox (Josh Duhamel) of the US Army and Technical Sergeant Robert Epps (Tyrese Gibson) of the US Air Force fought alongside the Autobots against the Decepticons in the first part. In The Revenge, they work, now promoted to the rank of major and. Master Sergeants promoted, for the NEST (Nonbiological Extraterrestrial Species Team) organization, which works with the Autobots to fend off further attacks by the Decepticons. Graham (Matthew Marsden) from the British Special Forces is a newcomer, but he only plays a supporting role in the film.
Theodore Galloway (John Benjamin Hickey) is the U.S. Government's security advisor and is critical of the alliance between Autobots and humans. As an intransigent bureaucrat, he thus causes trouble for Lennox, Epps and the entire NEST team.
General Morshower (Glenn Morshower) is the strategic leader of the NEST operation. Performer Glenn Morshower was already seen in the first part in the role of Colonel Sharp, but in The Revenge he plays a new character named after him.
Seymour Simmons (John Turturro) worked as a high-level agent for the government organization Sector Seven in the first film. After this was disbanded at the end of the film, in The Revenge he now works in his mother's butcher shop and runs the website "Giant Effing Robots" under the name "Robo-Warrior", which competes with Leo's site. Only when Leo asks his rival for help, Sam (and the viewer) learn that "Robo-Warrior" is Simmons.
A supporting role has Professor Colan (Rainn Wilson), Sam's college professor. Michael Bay said he based this character on one of his own instructors who was rumored to have seduced female students.
For none of the newly introduced characters there is a role model in previous Transformers series.
The leader of the Autobots is, as in the first part, Optimus Prime, who considers freedom the right of all sentient beings. Just like in the first part, in the sequel he again transforms into a long-hauled semitrailer, a Peterbilt 379. During the course of the film, Optimus "dies" but is brought back to life at the end, something that has often happened in a similar form in the various Transformers series.
Bumblebee is still Sam's protector. In contrast to the first film, at the end of which he regained his ability to speak, in Revenge he communicates again via his car radio and mechanical sounds. The companion comics from IDW Publishing try to explain this with a repeated battle injury, but in the movie itself the contradiction is not directly addressed. As in the first installment, Bumblebee transforms into a Chevrolet Camaro, now the 2009 production model in The Revenge.
Ironhide, Optimus Prime's weapons expert, transforms into a black GMC topkick pickup truck.
Ratchet, the Autobots' chief medic, transforms into a modified Hummer H2 search and rescue ambulance.
New additions include Skids and Mudflap, the "twins" who are relatively young and inexperienced compared to the rest of the Autobots, and frequently fight. At the beginning of the movie, the two still transform together into an ice cream truck, then later Skids transforms into a Chevrolet Beat (the prototype Chevrolet Spark) and Mudflap transforms into a Chevrolet Trax. The two bear the names of earlier Transformers characters, but otherwise have nothing in common with them. Sideswipe is the soldier among the Autobots. Transforms into a new Chevrolet Corvette Stingray concept design. Among other things, he helps kill Sideways in Shanghai. In the original series, Sideswipe still transformed into a Lamborghini Countach. Had a twin brother named Sunstreaker.
Arcee is a "female" Autobot made up of three independently acting robots, all three of which transform into motorcycles, a Ducati 848, a Suzuki B-King and an MV Agusta F4. The motorcycles were modified and painted for the film by the Retro SBK company. One of the robots is destroyed at the end of the movie, another one is severely damaged. Originally, it was planned that the three robots in the movie would have a collective consciousness and be able to combine into one big robot, but this idea was later scrapped again. In Hasbro's toy series, the robots are characterized as separate characters, one of which is named "Arcee" and the other two are named "Chromia" and "Elita-1". The holographic female drivers at the beginning of the film are embodied by Erin Naas, best known as a model from the American game show Deal or No Deal. The original Arcee made his first appearance in the 1986 animated film The Transformers: The Movie, transforming into a futuristic sports car. Originally, Arcee was already slated for the first part. However, the original film design was not used for The Revenge.
Jolt transforms into a blue Chevrolet Volt (the basis of the Opel Ampera, expected to be released in 2011) and is only seen very briefly in the film, helping Ratchet, among others, to connect Optimus Prime to the remains of Jetfire. Just like Skids and Mudflap, Jolt was reinvented for the film and simply uses the name of previous Transformers characters.
Jetfire is a very old Transformer in the film. As a "Seeker" ("Seeker"), he came to Earth a long time ago and later stored in a deactivated state, disguised as a Lockheed SR-71 Blackbird, in the Smithsonian National Air and Space Museum, until he is brought back to life by Sam. Although he was originally part of the Decepticons, he switched sides and supports the Autobots despite his poor condition. In the end, he sacrifices his life so Optimus Prime can use parts of him as a form of armor to fight The Fallen. In the various Transformers series, Jetfire transformed into various fictional and existing jets; in the original comic book and animated series (in the latter under the name "Skyfire"), he was also originally a Decepticon, just like in the movie, but soon switched sides. A physical connection between Optimus Prime and Jetfire, on the other hand, was first seen in the Transformers: Armada series, while the depiction of Jetfire as a "decrepit" robot was conceived specifically for Revenge.
Wheelie a.K.A. Wheels (he is called "Wheels" in the credits and in the scriptwriters' audio commentary on the DVD and Blu-ray versions of the film, but Hasbro's toy figures for the film are named "Wheelie", which Michael Bay also uses in his audio commentary) is one of the Decepticons' scouts and, disguised as a toy pickup truck, is tasked with stealing the Shard of the All Spark from Mikaela's custody. In the process, however, he is captured, and when he learns from Jetfire that he has a choice, he switches sides and joins the Autobots. Other than the name, Wheelie has little in common with his role model from the original series. In the German dubbed version of the film, he is called "Wheeler".
The Fallen is the new main antagonist in the film. One of the first Transformers ever, he betrayed his "brothers," the Primes, thousands of years ago in an attempt to destroy Earth's sun. His form of transformation, a type of alien aircraft, is seen only briefly in the film. According to actor Shia Labeouf, the relationship between Megatron and The Fallen is comparable to the relationship between Darth Vader and the Emperor from Star Wars, while producer Lorenzo di Bonaventura sees parallels between The Fallen and Judas Iscariot. The original version of The Fallen was created in 2003 for the comic book miniseries Transformers: The War Within (vol. 2) – The Dark Ages created from the publisher Dreamwave Productions, only years later Hasbro also released a toy figure modeled after the comic book character that transformed into a futuristic tank.
Megatron, the power-hungry leader of the Decepticons, was apparently killed at the end of the first part when Sam Witwicky pressed the All Spark Cube into his chest, but is brought back to life in The Revenge with the help of a shard of the Cube. In the first part, Megatron transformed into a kind of alien jet, in addition, in The Revenge he also transforms into a futuristic tank.
Starscream, Megatron's deputy, was one of the few Decepticons to survive the first part and escaped into space during the post-credits. He still transforms into an F-22 Raptor, but this time it is painted with alien symbols. In contrast to the first installment, Megatron's disdain for Starscream, which was a frequent feature in previous Transformers series, is made more apparent in The Revenge.
Soundwave, the Decepticons' communications expert, remains in Earth orbit throughout the film, connecting to a U.S. Military satellite. The original character from 1984 still transformed into a cassette recorder and in this form had minions that transformed into cassettes. In the movie only Ravage remains, then as now a mechanical panther, which is sent to Earth in the form of a rocket in the movie. Soundwave and Ravage were originally intended for the first part.
Alice (Isabel Lucas) disguises herself as a human college student and attempts to seduce Sam in this form. The character is remotely based on the "Pretender" Transformers that Hasbro introduced in 1988. In a cut scene used in the comic book adaptation of the film, this is explained by the fact that their "human" form is based on an "Alice in Wonderland" mockup from a theme park. The Constructicons transform into construction vehicles. Can join together to form a super robot called Devastator. In the film, the Constructicons exist in multiple forms, though it is not clear whether the construction vehicles that make up Devastator are actually individual robots or whether he merely splits into multiple vehicles that also serve as transformation forms for individual robots. Known by name (in some cases only via Hasbro's toy figures) are Demolishor and Scavenger, both O&K/Terex RH400 hydraulic excavators, though Demolishor is killed early in the film; Rampage, a Caterpillar D9L dozer; Mixmaster, a Mack concrete mixer; Hightower, a Kobelco CK2500 crawler crane; Long Haul, a Caterpillar 773B dump truck; Overload, an articulated dump truck; and Scrapper, a Caterpillar 992G wheel loader. Demolishor and Rampage are listed in the credits under their working names "Wheel-Bot" and "Skipjack", although Rampage is called by his name in the film itself. Devastator and the Constructicons also appeared in the original series, but some of them had different names there. One of them, "Bonecrusher", was already the name of a Decepticon in the first part, which turned into a Buffalo MPCV minesweeper. While this is not one of the Constructicons in the films, a doppelganger of Bonecrusher can be seen in Revenge, similar to the Constructicons that appear multiple times. In turn, the name "Devastator" was already used by a Decepticon in the first part, but both Hasbro and the screenwriters called this a "mistake" even then. Hasbro's toy figures for the film were called "Brawl" at the time.
Sideways, an Audi R8, is also killed early in the film. Similar to some other robot figures, Sideways was invented especially for the movie. Just uses the name of earlier Transformers characters.
The Doctor, a spider-like robot, is the Decepticons' "doctor" who brings Megatron back to life and later extracts information from Sam's brain. He transforms into a microscope. Hasbro's toy figure for the film bears the name "Scalpel".
Grindor bears a strong resemblance to Blackout from the first film, but unlike the latter it transforms not into a Sikorsky MH-53 Pave Low transport helicopter, but into a slightly larger model, a CH-53E Super Stallion. In the movie, he is killed by Optimus Prime.
Scorponok, a mechanical scorpion, possessed a symbiotic link with Blackout in the first film and escaped after fighting the U.S. Air Force in the Qatar desert. In Revenge, he returns during the final battle in the desert of Egypt, but is killed shortly after by Jetfire.