But that's what happened to Dana Fox while writing "What Happens in Vegas."

The big-screen comedy, which opens at 11:59 tonight (Vegas prime time), stars Cameron Diaz and Ashton Kutcher as party-hearty Vegas visitors who meet cute, marry in haste at a local wedding chapel -- and repent the morning after when one of them wins a $3 million jackpot with the other's quarter, triggering a fumin' feud that lasts until the inevitable happily-ever-after ending.

"I have a total love-hate relationship with Vegas," Fox cheerfully admits during a telephone interview to discuss the movie. "I think I hate it, but I really love it."

Every time Fox had to visit Las Vegas -- for a bachelorette bash, a birthday party or miscellaneous on-the-town blast -- she went along "against my will," but always ended up "having the greatest time ever."

And when the Las Vegas Convention and Visitors Authority's TV commercials popularized the phrase that became the movie's title, Fox wondered whether Vegas might provide a logical setting for a story line she was considering -- about a married couple, battling over a prenuptial agreement, who "get to know each other during their divorce."

It was "right around the time Britney Spears married that guy" (her hometown pal Jason Alexander -- not the guy from "Seinfeld") and had the marriage annulled within a few days of the January 2004 nuptials.

"Vegas is the only place on earth where you can make a really bad decision -- and win a ... load of money" at the same time," Fox says.

Indeed, if Las Vegas didn't exist, Hollywood might have to invent it, suggests the movie's director, Tom Vaughan.

"It fulfills a useful role for moviemakers," he says, because it's a perfect place to "take characters, spin them around and have them do crazy things."

Crazy things like the ones Jack (Kutcher) and Joy (Diaz) do once they hit the Strip.

He's a hang-loose dude who has just lost his job. She's a hard-charging Wall Street trader who has just been dumped by her fiance. And yes, these opposites do attract.

Fox describes Diaz's character as "a girl who's tightly wound and thinks she hates Vegas." That is, "her sentient self hates Vegas," the screenwriter adds. "Her true self loves Vegas." (Sound familiar?)

Ironically, most of "What Happens in Vegas" takes place not in Las Vegas but in the characters' hometown, New York.

But what happens here sets the stage for everything that comes afterward, including a barhop-'til-you-drop spree that sets the stage for Jack and Joy's subsequent relationship.

"People have a really transformative experience" when they hit Las Vegas, Fox maintains, in part because "Vegas makes you do things out of your comfort zone."

That assessment applies to movie crews as well as movie characters -- which explains why the Las Vegas portion of "What Happens in Vegas," which takes place at the beginning of the movie, was the last sequence to be filmed last fall.

It had to be that way, Vaughan says.

"From what I knew of Vegas and what I knew of film crews," the director says, "I thought, if we go there first, it may create strange tensions.' " So, he decided, "let's put that at the end."

By the time the cast and crew finally made it to Las Vegas, "everyone got to know each other" and cast members were "a bit freer. They needed to be kind of wild."

They had plenty of Las Vegas hot spots in which to be wild.

Planet Hollywood Resort, which also served as a primary location for this spring's blackjack-themed hit "21," provided the same sort of backdrop in "What Happens in Vegas."

The erstwhile Aladdin gave the production "a lot of flexibility," Vaughan notes. "They were willing to let us come and take over," even closing part of the casino during the shoot.

That wasn't enough to keep tourists away from the giant slot machine that delivers the movie's disputed jackpot, however.

"The prop guys enhanced it and it sat on the (casino) floor for a few days," Vaughan recalls. "I kept seeing people trying to play it."

The production also shot at the Palms (inside the Rain nightclub and outside at the pool), at Pure nightclub inside Caesars Palace and at Bellagio, where the filmmakers "got to control the Bellagio fountains," Vaughan recalls. "Now that's a power trip."

Overall, "I got everything I wanted from Vegas," the director says of the location shoot. Which was fortunate, he adds, because "What Happens in Atlantic City" just wouldn't have the same impact.

"It's on a scale not replicated anywhere else," Vaughan says of the movie's title town. "It's like you leave the rest of the world behind" when entering "the wonderland that is Las Vegas."

Yet for all of Las Vegas' exotic qualities, screenwriter Fox did love that it was universal," she says of the movie's scenario. "It could happen to everyone. As long as you're drunk and slutty and in Las Vegas," that is.

Fox's luck on the project held steady through casting and production.

"Luckily, the movie I set out to write -- it feels like that movie when I see it," Fox says. "I wanted it to feel more like comedy than romantic comedy -- and as edgy as possible, without being raunchy."

And as "What Happens in Vegas" made its way from script to screen, Fox made her peace with Las Vegas.

"I needed to admit my love for Las Vegas," she says. Now that she has, "it feels like hitting the jackpot."

Contact reporter Carol Cling at ccling@reviewjournal.com or 702-383-0272.