My fellow Americans, our long national nightmare is over. By that, I mean, naturally, that the auditions phase of “;American Idol”; has shuttered and this week we plummet, headlong, screaming and nauseous, into the greatest circus ever devised by reality television, Hollywood Week. There is simply nothing greater. Or more blood-curdling.

But first, let's reiterate the Two Immutable Laws of “;American Idol.”; Memorize them. Better yet, tattoo them on your feet so they're always visible whilst you're immersed in the spectacle:

1. “;American Idol”; is just a singing contest.

2. “;American Idol”; is not just a singing contest.

The auditions phase always seems to go on forever. The judges pop into a half-dozen mainland cities — apparently they've sworn off Hawaii forever — giving the impression they listen to stadiums-full of hopefuls. Actually, each entrant usually has a posse of family and friends, filling out the cast-of-thousands landscape, and there are apparently producer-judges who make snap decisions on who gets to appear before Simon/Randy/Kara/Guest Judge.

Who gets to stand on the auditions hot spot? Certainly not the vast majority of dull-average people with pleasant, ordinary voices. No. We're talking diamonds in the rough, with a sprinkling of coal and cinders. People who can actually sing, or have something going on vocally, equally balanced with entrants who are frankly unbalanced — the cruelly oblivious, the freaks, the closet dreamers, the tone-deaf pitifuls, the criminally un-self-aware and the sociopathic debris of a culture that equates hard-won talent with desperate lotto winnings. People who don't listen, and never will. People taught “;self-esteem”; in kindergarten.

Auditions. It's totally a grand parade, isn't it? Like that bargain bag of off-brand cheesy snacks, you can hate yourself afterward for consuming the whole thing, leaving nothing but orange fingers and a chemical aftertaste.

But, Hollywood Week. This week! It's the Holy Grail, Moby Dick and Tickle Me Elmo of reality television all wrapped up in one sweating, stage-flop, spooked and floundering mythical beast. It is the best of times precisely because it is the worst of times.

Hollywood Week is actually two weeks, oh joy! We get the contenders whittled down on Feb. 17, then it's a flaming death spiral cage match for the boys and girls until March 11, when the top 12 are revealed.

OUT OF THOUSANDS, 172 were given Golden Tickets to compete during Hollywood Week. By the miracle of videotape, these people auditioned several months ago. This week, “;American Idol”; moves into near-live programming, and some of these auditionees may have taken lessons, gotten makeovers or otherwise mutated in the interim. They may have changed, alas.

None are from Hawaii, although one guy was kidnapped by a fleeing parent and raised on Maui, and JB Ahfua of Utah appears reasonably Pacific.

Still, 172 hopefuls. And here's the harsh truth. They have to be whittled down to 24 — maybe 36 — by the end of the week. No exceptions. One slip-up, one muffed note, one wardrobe malfunction or snotty retort, and they're gone baby, back to Palookaville. Pressure's not only on, they're all in the steam pot together.

“;American Idol”; will throw it at them this week. Songs no one knows. Forced choreography. Chained-at-the-wrist teamwork. Sleep deprivation. Sneaky psychological tricks. Slavering hopefuls nipping at your heels. It's the gulag, and only the strong, the vicious and the lucky survive. Remember, again, the Two Immutable Laws of American Idol: You not only have to sing, you have to perform. Flinch, and you're gone, gone, gone.

Can't wait.

Is anyone suffering from Post-Paula Depression yet? The judges stand in for us, and so they are like family. Kara Dioguardi, with her atta-boy attitude, seems to have picked up the positive-vibe mantle, without Paula's zen weirdness. Randy Jackson still doesn't understand math (”;I say yes, one hundred million percent!”;) and makes faces instead of comments, which is somehow more eloquent.

During the auditions, guest judges sat in, as if auditioning themselves — Victoria “;Posh”; Beckham, stick-figure alien, resembling the Little Goatherder marionette from “;Sound of Music”; (she did give handy fashion advice to the clueless, however); Neil Patrick Harris, awesome and businesslike; musical munchkin Kristin Chenoweth; sullen teen idol Joe Jonas, as useless and as insubstantial as a waft of cigarette smoke.

The actual Paula replacement is Ellen DeGeneres, who debuts this week. But it's Simon Cowell who makes it all work; Simon, who always speaks the truth and sees right to the heart, no matter how difficult, whose British detachment cuts through gigantic swaths of self-delusion. You want to understand “;American Idol”;? Watch Simon. When you see dollar signs sparkling in his eyes, the magic is working. It's all about The Sell.

When Cowell leaves the show at the end of this season, it will be tough. The only possible replacement is “;Project Runway's”; Tim Gunn. Make it work.

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» Burl Burlingame will be writing weekly “;American Idol”; updates online.