“The Hangover” opens from the desert around Las Vegas. A man bleeds from his lip as he speaks into his cell phone. He instructs a faraway bride to hang up her bridal gown. She’s not going to need it. They don’t know where the groom has vanished.

This edgy scene suggests that if you eat to the center of this comedy, you will find a secret of darkest cherry – something bleak and probably a little depraved. The fact that “The Hangover” delivers nothing so tasty or devilish is its great misgiving.It’s our popular fantasy that Las Vegas beckons a sort of madness even within our most sedate personalities. The most accountant-y of accountants might for one night lose his mind. This seduction myth fuels “The Hangover,” as four friends head to Sin City for one last rodeo before one of them plunges into marriage.

The nice-guy groom Doug (Justin Bartha) is out for the traditional last blast, but in for a most untraditional one. The wiseguy teacher (Bradley Cooper) craves a long, refreshing party. Stu (Ed Helms), the neurotic dentist, needs an escape from his henpecking girlfriend for a few days. Then we have the maladjusted Alan (Zach Galifianakis), a shaggy-bearded chaos generator. Every time a scene needs saving (or killing), he can be counted on to drop his pants. Or say something weird. Or show off the dietary habits of a goat.

The friends wake up the next morning to a trashed Caesar Palace suite, completely wasted, without a shred of memory about, for example, how the live tiger got locked in the bathroom. And quicker than you can say Steve Guttenberg, they find a baby in the closet, its origin and purpose a total mystery. The dentist is missing a tooth, but that’s not all that is missing. The groom has disappeared without the benefit of a scream. For the next two days, the men struggle to stitch together their crazy night and save their missing friend from the neon clutches of Vegas.

If “The Hangover” had been made ten years ago, it might have been an indie directed with the offbeat spirit of a Doug Liman trip. Instead, it concedes too much of its touch of zaniness to its desire for a mass audience. Rather than ride along through the realm of the outrageous or profane, the film is left rubbing its eyes and piecing together the predictable. Sure, it might still be insane if a guy from your office capped off a drunken Vegas adventure by marrying a stripper. But it isn’t exactly a storytelling novelty.I’ll concede that the tiger caper, including the beast’s celebrity ownership, is one blind-squirrel instance of getting things right. But too much dangles.

In a wild comedy, a drunken hospital visit should end with something weird pulled out of someplace weird, not a mild case of bruised ribs. And why recycle the plot of “Three Men and a Baby,” only to surrender it without a punchline? Was there nothing different to do with the warmhearted stripper (an unaging Heather Graham)? Could you make her a graduate student paying her tuition, with the brains and sass to give the film a female perspective? The three female characters are a pole dancer, a fed-up bride, and a hellcat girlfriend. Like all modern male comedies, this one is coated in sexism.

Director Todd Phillips loves frat boy bonhomie. His cult hit “Old School” has taken up its spot in the “Animal House” pantheon. It would be wonderful to say that “The Hangover” captures that feeling of male bonding and ritualism, but it really doesn’t. From a friendship perspective, these guys all take their own separate cabs. If the search for a missing pal seems like an annoying distraction from a comedy routine for the men involved, why should it matter to the audience?

“The Hangover” goes to a great amount of effort to be almost-but-not quite funny. There are six or seven golden laughs, served with a fair side of smiles. No pain was involved. You won’t need aspirin or menudo the next morning. Yet if it were not for this era of all-bromance-all-the-time, I’m not sure that it ever would have been made.