LAST VEGAS (Rated PG-13)

What happens when four geriatric lifelong friends descend on Las Vegas for the ultimate bachelor party? Should we expect the old guys’ version of “The Hangover,” a wildly antic comedy or something more genial?

Given the amoral and enticing setting of Sin City, “Last Vegas” offers the requisite broad humor to be mined when old geezers find themselves seduced by the liberating excesses of the gambling oasis.

But there is much more to “Last Vegas” than the formulaic production of comedic fun. The geezers, Michael Douglas, Morgan Freeman, Robert De Niro and Kevin Kline, all of them a few years on either side of 70, are the reason to see this film.

The story begins when the quartet are youngsters and best pals running around Brooklyn, dubbing themselves “The Flatbush Four,” while hanging out at the local soda fountain and dodging the local bully.

Fast forward about six decades, the old friends, though separated by geography, remain connected. Douglas’ Billy is a slick Malibu lawyer about to marry a girl more than half his age. He wants his childhood buddies at the Vegas wedding.

Freeman’s Archie is a widower living in New Jersey with his son’s family. Having survived a stroke, Archie has to deal with his overprotective son who won’t even let him out of the house.

Down in Florida, Kline’s Sam, still married after 40 years to the same woman, is retired and bored, suffering from the lack of spark in his marital relationship. At the airport, his wife gives him a surprise going-away gift, something like a free pass.

Having lost his wife recently, De Niro’s Paddy, a cynical, grumpy old man, has become a recluse, hardly ever venturing from his New York apartment. It takes some cajoling to get him on an airplane for any reason.

There’s an old rivalry between Paddy and the soon-to-be married Billy. Having to do with competing for the same girl long ago, the simmering tensions come to the fore when Billy and Paddy meet lovely lounge singer Diana (Mary Steenburgen).

Mature and wise, as well as beautiful and sexy, Diana develops a special affinity for both Paddy and Billy, though for different reasons. This serves to reignite an old grudge that had previously divided the two childhood pals.

Inside one of the ritzy hotel casinos, Archie gets extremely lucky at the blackjack table, earning the group the unlikely distinction of VIP players. They end up with complimentary accommodations in the most posh suite that had been reserved for rap star 50 Cent.

While playing cards, the boys attract contempt from obnoxious frat boy Dean (Jerry Ferrara), who quickly changes his tune after he comes to believe the foursome are part of the East Coast mob. Getting special treatment at a casino can do wonders.

Once convinced the old guys are actually wise guys, Dean transforms from being an insufferable jerk to their gopher, fetching luggage and drinks and eventually coordinating the bachelor party blowout in the hotel suite.

Leading up to the wild party, the boys get some quality Vegas time by hanging out as the only attentive customers at Diana’s lounge and judging a biking contest where every pretty girl rates a “10” in their considered judgment.

On the prowl, Sam becomes friends with a Madonna impersonator (Roger Bart) and other drag queens, and then later meets an eager young pretty girl who is attracted to his worldly maturity.

For the most part, the passing of time has had a way of ossifying the quartet into a sedate maturity far removed from their hell-raising youthful exuberance. Except that Billy, the wealthy playboy, seems not to have mellowed in any significant way.

Being in Las Vegas has a way of bringing the boys out of the collective funk of old age dullness. Archie cuts loose after consuming vodka and Red Bull, finally getting to enjoy a great turn on the dance floor.

Sam loosens up enough to realize that retirement doesn’t have to be a dead-end. Meanwhile, the cranky Paddy evolves from a frowning pessimist to being willing to give his life a second chance at some joy.

The real joy of “Last Vegas” is watching the talented quartet of old guys putting some juice and excitement into the slogan “Old Guys Rule.” My guess is that you could have turned these veterans loose with the barest sketch and they’d come up with some interesting improvisation.

“Last Vegas” is appealing for its laughs and hijinks, maybe more so for folks who don’t mind the stale jokes about Lipitor, Viagra and assorted medical conditions. This is an entertainment skewing for the older demographic, though I believe it should be enjoyed by a wide audience.

Above all, “Last Vegas” is an amiable comedy that delivers tried-and-true themes that are best realized by gifted pros. And that’s what you get from Morgan Freeman, Michael Douglas, Kevin Kline and Robert De Niro.

Tim Riley writes film and television reviews for Lake County News.