A Transformer is a bizarre technological amalgamation of non-descript heaps of metal mashed onto one another, forming a behemoth warrior-robot. Despite how disjointed, ridiculous and incoherent its metallic components look, the sheer spectacle and grandiosity of the Transformer assuages any initial misgivings. Their newest film, "Transformers 2: Revenge of the Fallen," is also disjointed, ridiculous and incoherent, but the mere spectacle of the plot saves it from utter absurdity.

At first, the world seems more peaceful after the evil Transformers, known as the Decepticons, lose their one-dimensional overlord, Megatron. The lead character, Sam Witwicky (Shia LeBeouf), must have had a wonderful college admissions essay where he discussed saving the world with his Autobot pals (the noble Transformers), because he is accepted to Generic Mc'Ivy League University. Sam realizes that some mysterious rock shard in his jacket is infused with arcane powers, and he soon professes to see symbols that nobody else can. A pleasant side-effect of his hallucinogenic episodes is intellectual brilliance: He disproves Einstein's Theory of General Relativity after perusing his 900-page astronomy textbook in 10 seconds. For the viewer, side-effects include the strong desire to roll one's eyes.

But hell breaks loose when Sam discovers that the Decepticons are after his shard, which turns out to hold the secret to a primordial vault that holds a powerful Transformers artifact. (Silly enough, the robots who transform into Camaro sports cars and toasters are, in fact, eons older than the human race). After Sam's voluptuous tomboy girlfriend, Mikaela (Megan Fox), joins the fray, the pair teams with the benevolent Autobots to prevent the Decepticons from doing the expectedly unexpected: destroying the Sun. The stakes are raised when hero-robot Optimus Prime is killed, and the arch-robot-nemesis Megatron is revived.

The plot skids off-track when Sam and Mikaela, along with two homoerotic companions, are hounded by a weakened Autobot force, a Decepticon resurgence and a bureaucratically hamstrung US Army. In a last ditch effort, Sam uses the symbols he's been imagining to help him locate the vault, taking him to Petra in Jordan and the Great Pyramids of Egypt, both of which were built by the robots.

When Sam finally finds the vault and discovers its magical pixie dust, he realizes he can use the dust to revive Optimus Prime and tip the balance of power back to the Autobots. The problem is Optimus Prime's corpse is laying in the middle of the desert and the Decepticons are staking out the corpse as a trap. An exhilarating hour-long fracas of knock-'em-sock-'em robots ensues as the hunks of metal duke it out. Annoyingly, Sam and Mikaela always manage to jump at the last, safest moment, their heels slightly charred by massive fireballs wrought by the pursuing Decepticons.

While the fate of the world is in the hands of a horny 5'9" adolescent, "Revenge of the Fallen" provides overused slap-stick comic relief to tone down the hopelessness of the protagonist's quest. A Wall-E inspired mini-Decepticon humps Mikaela's leg, Sam's dogs hump each other while kitchen-appliance Decepticons bedevil the Witwicky household, and viewers are reminded to drink Mountain Dew when the film features a dorm room's Mountain Dew soda machine. (In the first film, one robot transformed from a Mountain Dew soda machine and shot soda cans.)

Despite the ridiculous plot, the film's flashy CGI graphics and sex-pumped cast juice up our more basic desires and leave our disbelief checked at the door. It's easy to get lost in the visceral clash of monster-metal, in the same way a monster-truck race entertains with its crush of metal against gigantic rubber wheels. This movie's nothing but metal and fury, signifying nothing, but is spectacular nonetheless.