And then there's that rarified stratum of the awesomely preposterous, solely occupied by chicks in skintight, gold-lamé bodysuits with gigantic Mohawk manes that look like the spoils from a scalped Mr. Ed.

Enter Janet Jackson.

Exit prudence.

And good riddance, by the way.

At the Mandalay Bay Events Center on Friday for a stop on her "Rock Witchu Tour," her first in seven years, Jackson didn't just jump the shark; she pole-vaulted over the thing and then thumbed her nose at it from on high.

"Obey me," she growled during a pretaped video interlude that played on a huge projection screen behind the stage early in the show. With black lipstick, snarling at the camera, this was the "Bad Janet."

Or something.

Shortly thereafter, we saw her face bathed in white light, awash with celestial radiance.

This was the "Good Janet," we presume.

What followed was a musical parable on the eternal struggle between the forces of evil and righteousness.

That, and some shirtless dudes spinning on their heads, stuff blowing up and lots of extras in sailor get-ups, gyrating to the rhythm.

It was a lot to take in, and Jackson gave the adoring crowd plenty to chew on. She performed all or portions of more than 30 songs during a show spanning two-plus hours.

It began with a slew of early hits -- including "Pleasure Principle," "Control" and "What Have You Done For Me Lately" -- that established Jackson among the more self-assertive female popsters of her era some two decades ago.

Those songs have a common theme, delivered over a whiplash beat: "I don't wanna rule the world; just wanna run my life."

And what better way to truly flaunt her independence than to revel in her idiosyncrasies like a kid gorging on Halloween candy, be it rocking the stage in shiny combat boots or adopting this alter ego or that?

The first words she sang on this night: "You might think I'm crazy, but I'm serious."

That sentiment would pretty much encapsulate the entire evening.

As she's matured, the tone of Jackson's albums have changed a bit. She's more aggressively sexual these days, more outwardly libidinal, and her show reflects as much.

During "Discipline," the slinky, heavy-breathing title cut to her latest album, she brought a dude out on stage and served as a purring dominatrix, wrapping fabric around his throat and pulling it tight.

As that scene indicated, this was as much a night of sweaty performance art as it was a larger-than-life pop show, with Jackson taking the stage alone at first, without the oversized backing band that most contemporary singers employ to lard up their tunes live.

As drawn to the overblown as she is, Jackson's sharp enough to realize the value of restraint here and there, and though her concerts pulse with all manners of visual ostentation, she doesn't overindulge in vocal acrobatics like so many of her peers, her voice soft yet commanding and as malleable as the goo inside a lava lamp.

She'll whisper through a wistful ballad, her voice delicate as porcelain ("Never Letchu Go") then growl through a storming rocker like "Black Cat," where she brought out a hard-hitting backing band near show's end.

Through it all, the razzle-dazzle seldom ebbed, especially during a climactic "Rhythm Nation," when a mammoth wall of sparks rained down from the rafters.

"Let's wait awhile before we go too far," Jackson had sung sweetly earlier in the evening, during the doe-eyed ballad "Let's Wait Awhile."

But, by this point, Ms. Jackson, it was a little late for that.

Contact Jason Bracelin at 383-0476 or e-mail him at jbracelin@reviewjournal.com.