TRANSFORMERS: REVENGE OF THE FALLEN — ★★ — Shia LaBeouf, Megan Fox; rated PG-13 (violence, vulgarity, profanity, drugs, torture, brief sex, slurs, nude art); in general release

All director Michael Bay and his screenwriter team need to do in "Transformers: Revenge of the Fallen" is get us to the point where the giant robots show up and start smashing things and blowing them up.

After all, there was already one "Transformers" movie — this one's 2007 predecessor, which set up the premise and gave audiences an introduction to the characters.

But strangely enough, Bay and the screenwriters (which include two of the scribes of the recent "Star Trek" re-imagining) actually try to tell more story here.

That's a big misstep, because if anything, the plot is too convoluted and confusing, and there's too much juvenilia for the good of the movie.

That's a shame, because the computer-generated visual effects are stunning, and there's plenty of action.

This sequel picks up the story two years later. Heroic human Sam Witwicky (Shia LaBeouf) is going away to college.

His parents (Kevin Dunn and Julie White) are trying to hide their obvious sadness, and as expected, there's some relationship strain with Sam's gear-head girlfriend, Mikaela (Megan Fox).

And Sam's good-guy Autobots pals are sorry to see him go. Especially since Optimus Prime fears something bad is coming.

He's right. The evil Decepticons are still out there, trying to revive their leader, Megatron. His master, the Fallen, is also biding his time before he exacts his vengeance on mankind.

Again, there are a few exciting bits (such as Optimus Prime taking on an entire Decepticon army). But at two-plus hours, it's simply too long.

The dubious, tasteless humor and awful dialogue don't help. Neither does having a leading lady who can't act — Fox seems to be regressing in her development as a performer.

Bay and the screenwriters also find more humiliating things for returning supporting cast member John Turturro to do.

"Transformers: Revenge of the Fallen" is rated PG-13 and features strong violent content (robotic attacks, gunplay and shootings, explosive and vehicular mayhem, and violence against women), crude humor and references (sight gags and jokes about bodily and sexual functions), occasional profanity, drug use and references (marijuana), a scene of interrogations, brief sexual contact, derogatory language and slurs, glimpses of nude paintings and statues and some revealing undergarments. Running time: 147 minutes.

E-mail: jeff@desnews.com