"Transformers" is a wet dream for fanboys, with vehicles that whiz and whir into alien robots, spectacular sci-fi stunt chases, glistening military hardware, overheated computer software and brainy, hot girls who love Popular Mechanics.

It's a Michael Bay movie based on a Hasbro line of toys that perfectly captures adolescent fascination with mechanical things you can take apart and put back together.

The movie is noisy fun, with characters and plot lines kept simple and flashes of comedy that hit home more often than not. Most importantly, the filmmakers have shrewdly selected their young cast. Shia LaBeouf is one of the hottest young actors on the planet at the moment, with the surprise hit thriller "Disturbia" and excellent lead vocal performance in the animated comedy "Surf's Up" already behind him in 2007. Megan Fox and Rachael Taylor add terrific sex appeal in roles designed to emphasize female capability and intelligence. And singer-actor Tyrese Gibson and Josh Duhamel are the smart-looking military dudes who take on the aliens at street level.

The movie's appeal will definitely expand beyond fanboys and sci-fi addicts to include older "kids" who grew up with the Transformers toys and comic books. DreamWorks and Paramount should be well-rewarded for their deep-pocketed faith in this potential franchise with a global hit.

This is not the first cinematic outing for the mechanical warriors. A 1986 animated movie was based on the original "Transformers" television show, which was based, of course, on the popular multiform robot toy line. It didn't go over well at the boxoffice. (That tooner, incidentally, was set in 2005.) But now Bay and an army of visual designers have successfully re-imagined a photorealistic world in which these Titans can believably clash.

The best thing in the script by Roberto Orci and Alex Kurtzman (from a story by Orci, Kurtzman and John Rogers) is how a teen plot line gets tied into the fate of the world. Young Sam Witwicky (LaBeouf), who's nerdy but funny and sort of cool, gets a mysterious car from his dad, a banged-up '76 Chevy Camaro that he only later discovers is an alien robot. Now that's an intriguing way to get a girl's attention!

That girl, with the arresting name of Mikaela (Fox), has been in school with him for years but never really noticed him. One day she accepts a ride from him and finds herself caught up in a war of the worlds. Seems an ancestor of Sam made a discovery in the Arctic Circle that prompts the bad guys -- sorry, robots -- to target Sam, who unknowingly holds the key to mankind's survival -- if he hasn't already sold it on eBay.

Two robotic races -- the evil Decepticons and the heroic Autobots -- hide out on Earth as cars, trucks, 18-wheeler tractors, Hummers, jets or even a boom box before grinding and expanding into their robotic essence. These are CGI-errific moments, courtesy of Industrial Light + Magic, that will have fanboys leaping from their seats. All these techno creatures have feelings and emotions, you understand, which leads to the film's most amusing moment, when Sam's Camaro performs wheelies after his girlfriend "insults" the car. Its radio also plays tunes that fit the mood!

The filmmakers create three other sets of characters: A group of computer hackers headed by Taylor and Anthony Anderson, who no less than the U.S. Secretary of Defense (Jon Voight) desperately appoints as his "advisors"; surviving military members of an alien attack on a U.S. base in the Middle East, lead by Duhamel and Gibson, who somehow wind up duking it out with the aliens in downtown Los Angeles; and shadowy anti-alien agents lead by John Turturro.

The snarl of action and story lines is sometimes awkward, but at least the audience can identify with characters wherever the robots choose to rumble. No faceless multitudes screaming and fleeing here as in the Godzilla movies of old.

Clearly, none of this would work if Bay had not adroitly coordinated the stunts, animation and characters, both real and mechanical. Thanks goes to a team of editors, who have made good sense of all the action. On the debit side, sound levels are all too high, and the score pushes harder than necessary.

While he has long been a master of mayhem, on this occasion Bay weds his visual dazzle to material that carries the action smoothly. This is an extravaganza rather than overwrought excess. As one young boy exclaims upon seeing his first robot, "This is 10 times cooler than 'Armageddon'!"