Yes, it's loud, explosive and silly, but it also perfectly embodies the concept of a summer blockbuster with its simple good-guys-vs.-bad-guys plot, cheeky humor and flawless special effects. Transformers, opening tonight in many theaters, is easily the best movie based on an adaptation of a cartoon TV series.

Though it's at least 20 minutes too long and uneven dramatically (can you even say drama and Transformers in the same sentence?), the acting is sharp, and it features some of the most spectacular action and effects sequences of any movie of its kind.

The sum total of director Michael Bay's work has been spotty at best (The Island, Armageddon), but he made an inspired choice in casting the young, charismatic Everyman Shia LaBeouf (Disturbia). And surely the involvement of Steven Spielberg brings heft and sizzle to the entire production. Also, there are pleasant surprises in the supporting cast: an eccentrically creepy John Turturro, a likable Anthony Anderson and a valiant turn by Josh Duhamel.

LaBeouf stars as high school student Sam Witwicky, who buys his first car, a dented yellow Camaro that turns out to be an Autobot named Bumblebee. The car helps Sam team up with the object of his fantasies, Mikaela (Megan Fox). So much for the human story.

Meanwhile, other Autobots come from distant planets in search of the Allspark, which grants total power to anyone who possesses it. The Autobots are fending off the evil Decepticons. Each side wants to get their robotic limbs on the Allspark, which was stashed on Earth years before and found by Sam's great-grandfather on an Arctic expedition. Sam is unaware of his ancestor's role in the struggle between gargantuan space robots.

Earlier, a Decepticon taking the form of a fighter jet attacks a U.S. military base in Qatar, where soldiers including Duhamel and Tyrese Gibson wage an eye-poppingly explosive battle against an enemy they don't understand.

Turturro heads up a top-secret organization aimed at destroying the robots. He and his minions show up unexpectedly at Sam's house and whisk him away. This and the scenes that lead up to it, while the 'bots try to hide out in suburbia, are dazzling and quite comical.

The story falters during the protracted climax, but what remains is potent — sheer mindless fun and excitement. As a character watching the robots wreak havoc says: "This is 100 times better than Armageddon."