Rating:

A disaster of epic proportions, “Transformers: Revenge of the Fallen” represents a new low in director Michael Bay’s descent into self-parody. It’s more of what we’ve come to expect from Bay: more explosions than people, endlessly bombastic music, and a plot that’s simultaneously exceedingly complex and confoundingly boring.

The worst thing about the movie, out of many, is that it takes a $200 million budget and a two-and-a-half hour running time, and not a single memorable, impressive or fun thing happens. In a 15-second throwaway scene, two of the good robots briefly fight each other. I couldn’t help thinking, “Wow, with what they spent on that moment, which is totally incidental to the plot, DreamWorks could’ve bankrolled five or six decent indie movies.”

Coming two years after the original hit, adapted from the 1980s toy line and cartoon, “Revenge of the Fallen” continues the saga of an intergalactic civil war between rival robot races the Autobots and Decepticons. They’re all back, along with nerd hero Sam (Shia LaBeouf) and his improbably attractive girlfriend Mikaela (Megan Fox).

The entire reason for the robot feud, along with the McGuffin, is shrouded in exceedingly complex exposition. The scene in which an airplane at the Smithsonian, who had just been turned into a robot, gives a nearly five-minute speech explaining the plot was one of the few times in the movie I actually laughed.

For a movie about fighting robots, the script — by Roberto Orci, Alex Kurtzman, Ehren Kruger — is so needlessly complicated and nonsensical that it’s almost mind-boggling. Its attempts at humor also fail almost across the board, with the worst part of all being the pair of Jar Jar Binks-like “comic relief” robots that go way beyond the line of racist caricature.

At one moment, the Decepticons declare that they’re “done hiding,” and are ready to take their battle for the planet public. This is because we’re supposed to think the existence of the war between two races of giant robots has been kept a secret from the human population, despite their penchant for getting into destructive, explosion-filled brawls in broad daylight. The film is filled with inconsistencies like that, that might be paradoxical if we actually cared.

Bay, thankfully, seems to have gotten over his shaky-cam fetish; the original “Transformers” was arguably the worst offender ever of the decade’s most annoying film trend. But that doesn’t mean the action sequences are actually exciting. In fact, they’re boring and unimaginative.

Here’s the problem with the robots: they’re not that cool. They’re large and unwieldy, and it’s not that fun to watch them fight each other. And not only that, but there are about 20 of them, and with only a couple of exceptions, there’s nothing to distinguish one from another.

It all leads up to a 45-minute finale in which the Decepticons are confronted in the Egyptian desert by the Autobots, the U.S. military, the Jordanian air force, and the Sam/Mikaela team. It’s a widespread coalition using overwhelming force, so give the movie this — it believes in the Powell Doctrine.

Shia LaBeouf is a likable and engaging leading man, but he has not been in a single good movie as an adult. As for Fox, she got a whole lot of attention since the first movie, but it’s fair to say it wasn’t for her skill as an actress. Here, she gives every line reading with the same blank, dead expression, regardless of the situation. The Angelina Jolie comparisons are way off; Fox is actually the next Denise Richards.

This has been a pretty good summer for blockbusters so far — “Star Trek” was great, “Up” was one of the best Pixar films, “The Hangover” was an instant comedy classic, and even “Angels and Demons” wasn’t that bad. But the streak skids to a halt with “Revenge of the Fallen,” which fails on just about every conceivable level.