Did you hear about the "Break-Up" premiere last week? No? What a night. A red carpet was involved. City blocks were closed off. Jennifer Aniston looked ravishing--or, at least, as ravishing as a woman can look when she's surrounded by a hulking security team shielding her from a pack of teenage girls. Jen and her costar, Vince Vaughn, arrived separately, posed for photos separately and left separately, which was widely interpreted as evidence that they are so sleeping together. Four days later, it was party time again. Disney and Pixar shelled out $1.5 million to rent out a North Carolina racetrack for their premiere of "Cars." The animated film, which opens on June 9, is principally for young children, an audience for whom a red carpet isn't a big deal, just one more place you absolutely cannot pee.

Once upon a time, the classic Hollywood premiere--red carpet, flashbulbs, stars galore--was a sparkling symbol of the industry's glamour and exclusivity. Now they're publicity stunts, no more, no less, and expensive ones at that. Though a perfect-ly serviceable premiere can be arranged for about $100,000, most cost at least three times that. A "destination" premiere--when a studio holds its official U.S. launch outside of New York or Los Angeles--can send the bill soaring into seven figures. In 1998 Disney and producer Jerry Bruckheimer set the unofficial record with their gala premiere for "Pearl Harbor," which they staged on an aircraft carrier in Hawaii. The price tag was said to be $5 million. (Disney declined to comment.) When the top prize for such events is 30 seconds on "Entertainment Tonight," can they really be worth the money? Says one veteran studio publicity director: "I could put a red carpet outside my office and get the same amount of press."

But that wouldn't be nearly as much fun, and the saving grace of premieres is that everyone's having a good time. Right? "Going to a premiere is the last thing I want to do," says Amanda Lundberg, a partner at the PR firm the Dart Group and a veteran of two studios. "I don't know anyone who thinks premieres are fun. There's a lot of pressure, a lot of long hours. And my feeling is, when my clients are there, they're not having fun either, because it's work." On the surface, it seems like doing red-carpet press would be a relief for most celebrities. No one's invading your privacy, and if Isaac Mizrahi gets overly familiar, you can just keep walking. But not all stars see it that way. "They're vulnerable out there," says Dennis Rice, head of publicity for Disney's Buena Vista Pictures. "Maybe they had a funny expression on their face, or they accidentally have a boob pop out. Next thing you know it's on 'Access Hollywood' and all over the Internet."

Premieres have reached such a postmodern degree of non-event eventness that the movie itself--the "premiere" part of the premiere--is now the most insignificant portion of the night. Most critics have already seen the film, as have studio executives. Last year 20th Century Fox held a premiere for "The Fantastic Four" that went so comically awry, it's already the stuff of legend. The studio hired a boat to transport everyone--cast, crew, media--out to New York's Liberty Island for a screening, but a massive storm hit. Everyone was drenched. Then, 15 minutes into the screening, the film projector broke. "I remember thinking that it was irrelevant that no one saw the movie," says Bradley Jacobs, of Us Weekly. "Everyone got their pictures. The paparazzi, all the celebrity TV shows got what they needed." And here's the kicker: "The Fantastic Four" was a hit anyway. So if a disastrous premiere can't hurt a film, how much can a successful one really help?

Even proponents of the form seem to damn it with faint praise. "It's tough from everybody's vantage point--whether it's summoning the energy to smile for a few hours or going through the logistics of shutting down Hollywood Boulevard--but I do think it's still worth it," says Rice. "It's the icing on the cake after all of our advertising." If a premiere generates enough press, the theory goes, it'll do more good than the two or three prime-time TV ads that could've been bought with the same money. But even if "Access Hollywood" does bestow 30 seconds on your premiere, does that really suggest it finds it fascinating? You know what gets 30 seconds on ESPN's "SportsCenter"? Hockey.

Back in Hollywood's golden age, premieres weren't simply a means to an end. They were the embodiment of Tinseltown prestige. "You would have 60 stars at a premiere. Everybody under contract at the studio went: Judy Garland, Mickey Rooney, Peter Lawford, Clark Gable," says actress Debbie Reynolds, who still fondly recalls her first red-carpet premiere: "Singin' in the Rain" in 1952. Her date, arranged by the studio, was Robert Wagner. "The most handsome boy under contract at Fox," she says.

And today? "It's sort of blasé and corny now to go to a premiere," Reynolds says. After all, how special can it feel when everything from "Aeon Flux" to "Zathura" gets a red carpet? And even if a film is worthy of the fuss, its premiere won't attract anywhere close to 60 stars. "What happens is you send an invitation to, say, Betty Boop--and Betty Boop's assistant comes," says one studio publicist who has arranged many premieres. "So sometimes the studios will send cars for the high-profile people they've invited, and if that person doesn't come out to the car--if it's their assistant or whatever--then the car leaves empty. I'm not kidding."

Premieres may seem profligate--especially by the time the cast has "partied" in London, Paris, Tokyo, Berlin and Dubrovnik--but try telling an A-lister he's not getting one. "Some people like insane, lavish parties," says director Judd Apatow ("The 40-Year-Old Virgin"). "You have to have the Black Eyed Peas--I'm sure there are some people who consider it an insult if you don't." But does wanting a little party make you a monster? Surely not. "If my studio told me I couldn't have a premiere for my film, yes, I'd be offended," says Apatow. "On some level, a premiere is a thank-you for working really hard for a few years." Then again, he says, "my premieres aren't that expensive because I don't do them on a battleship. I just have some Chinese food in a large room." If your movie's worth watching, do you really owe people anything else?

Graphic: 5 RULES FOR THE RED CARPET: Fame ain't easy. We asked top publicists for tips on how to stay cool under the klieg lights.
Graphic: 1) Kiss Isaac. Mizrahi's in, Joan Rivers is out. "She's rude," says one publicist. "And she works for the TV Guide channel, so why bother?"
Graphic: 2) Pack a Sharpie. Break from the carpet and go sign autographs. You earn points with the crowd, and give the paparazzi a better photo.
Graphic: 3) Don't leapfrog. It's bad etiquette to jump ahead of another celeb if you're both doing press.
Graphic: 4) Unless it's Clooney. George is known to spend a long time answering questions. Charming, but it'll kill your pace. Pass him. He won't notice.
Graphic: 5) Skip the movie. No one actually stays to watch the film. When the lights go down, slip out the side exit, where your car is waiting.

With SEAN SMITH, JAC CHEBATORIS and RAMIN SETOODEH