Optimus Prime considers opening up a can of whoop-ass on Michael Bay for screwing up his sequel.

I'm not going to spend much time detailing the plot. It's way too convoluted, which is one of the picture's fatal flaws. Trying to describe it would be frustrating - for me, in trying to explain it, and for you, in trying to make sense of it. I'll just say that Sam Witwicky (Shia LeBeouf) is college-bound and figuring the most difficult challenge in his life will be staying in contact with girlfriend Mikaela (Megan Fox). Then he finds a shard from the "All-Spark" - the gizmo that turns machines into giant robots. The shard is desired by an evil Decepticon (bad robot) because it will give his faction a massive leg up in their intergalactic war with the Autobots (good robots) and destroy Earth in the process.

There's a lot more to it than that. A whole lot more. The Decepticons chase Sam and Mikaela all over the globe, while U.S. soldiers Lennox (Josh Duhamel) and Epps (Tyrese Gibson) try to figure out a way to organize a military strike, and head Autobot Optimus Prime attempts to help Sam understand the strange symbols he's obsessively seeing in his head, and a robot who can appear human stalks him and…oh, I give up.

Some new characters are introduced, most notably two Autobots named Skids and Mudflap. In what has to be the most egregiously racist thing I've seen on-screen in ages, the robots are presented as the worst possible stereotype of African-Americans. Seriously, if Stepin Fetchit was a robot, he would be Skids or Mudflap. The 'bots have tiny heads with humongous ears, and one of them has two great big buck teeth, one of which is gold. They talk in ebonics, strike hip-hop postures, and fist-bump each other. It blows my mind that, in 2009, no one - no one - associated with Transformers put the brakes on this. Not Bay, not the producers, not the special effects people, not the studio heads, nobody.

There's a lot more I could criticize about the film: it's too long (147 minutes) and too loud, and at times it's hard to tell which robots are good and which are bad in the hyperactively-edited action sequences. But I'm not going to do that in depth because, for me, the bottom line is that Transformers: Revenge of the Fallen simply wasn't enough fun. The original was effective because they got the story just right; watching it brought back the feelings I had as a child playing with my action figures and dreaming up the most incredible adventures for them to embark on. Some people griped that the movie was too juvenile, but that's part of what made it effective. A movie based on a line of toys should capture the youthful sense of an imagination at play.

The sequel has very little of that. There's no doubt that Bay and his screenwriters had one intention: to paraphrase Spinal Tap, they wanted to turn everything up to 11. Transformers: ROTF is bigger, faster, louder, and more manic than its predecessor. What they failed to understand is that sometimes less is more. The original had a nice mix of character, story, and humor, while the action scenes managed to be fast and furious without overstaying their welcome. In their zeal to give us more of what they think we want, Bay and crew have sucked all the joy out of their own franchise. The movie is weighed down by its own self-satisfied bloat.

Just look at the grand finale. The movie's final 45 minutes are set in the Egyptian desert where the Autobots finally face down the Decepticons. You may remember that the original had a battle royale on L.A. city streets at the end, and it was a highlight. Here, the movie keeps starting the battle royale only to interrupt it repeatedly. The robots start to fight, then we switch to scenes of the military planning a strategy. The robots fight some more, then we switch to some domestic drama with Sam and Mikaela, or with Sam and his parents. The robots continue fighting, then we switch to something involving former government alien hunter Simmons (John Turturro). The flow of the action is continually halted so that we never get the all-out robot war that we've been waiting so long to see.

I did enjoy a few things about Transformers: ROTF. The special effects are quite good, especially in a scene involving some Decepticons disassembling the pyramids. The moments where we do see some uninterrupted robot fighting are cool. Even a few of the concepts are interesting, most notably a bit set at the Smithsonian Air & Space Museum (which is getting a lot of play on movie screens this summer, what with this picture and the second Night at the Museum).

Some sporadic enjoyment aside, this sequel as a whole represents a significant drop in quality from the original. Transformers aimed only to give audiences the most entertaining ride possible. Transformers: Revenge of the Fallen practically bullies you into enjoying yourself. In real-world terms, it's the equivalent of that wedding DJ who just won't stop badgering people until everyone is on the dance floor. And we all know how we feel about that guy.

( out of four)

Transformers: Revenge of the Fallen is rated PG-13 for intense sequences of sci-fi action violence, language, some crude and sexual material, and brief drug material. The running time is 2 hours and 27 minutes.