How many tired old people jokes – and you know what; just tired jokes in general – can be wedged into a script before the audience attempts to drown themselves in butter flavoring? This is the difficult question proposed by the new oh-those-goofy-geezers comedy "Last Vegas" – or as I’ve been calling it with all-too-smug satisfaction, "The Hangolder."

As seen in an unconvincing sepia tone opening flashback, Billy, Archie, Paddy and Sam are old childhood friends, fighting off leather jacket bullies, cutely flirting with the lone girl in their posse and gleefully causing good-natured havoc.

Cut to 59 years later, and the boys have both changed a lot and not at all. Billy (a distractingly orange Michael Douglas) is now a wealthy playboy, desperately clinging to youth. In his desperation, he accidentally proposes to his hot younger girlfriend at a colleague’s funeral. She says yes, which means it’s time to get the four guys together – the Flatbush Four, as they were nicknamed – for a bachelor party in Vegas (because that’s what they did in "The Hangover," and that movie made a lot of money).

Archie (Morgan Freeman) and Sam (Kevin Kline) aren’t particularly hard to convince. The former is stuck watching terrible TV while under house arrest by his overly worried son (Michael Ealy), while the latter is in Florida, nursing his now mechanical joints alongside the wrinkliest senior citizens the casting director could find. That the first shot of Sam’s retirement home is aged flab bouncing in a pool is a bad omen for the kind of jokes to come.

The only member of the crew who requires some convincing is Paddy (Robert De Niro, returning to bored self-parody), the gang’s tough guy with a heart who’s gone into seclusion in his apartment after his wife passed away and has grown bitter toward Billy. After a quick visit and some nice acting from Sam and Archie, however, they manage to get him on board to Vegas.

When the guys finally land in Sin City, director Jon Turteltaub’s (the "National Treasure" movies, "Cool Runnings") film abandons pretty much any consistent story and turns into a loose assemblage of creaky, predictable jokes, most of which can be lumped into a category titled "Oh, old people!" (for maximum effect, say that while putting your hands on your hips with a warm, knowing smile).

Thanks to Archie winning a heap of money at the blackjack table without seemingly realizing it, the guys get to judge a swimsuit competition hosted by LMFAO’s Redfoo (what?! They’re not supposed to do that! They’re old!), manage to swindle the hotel’s swanky high roller suite from 50 Cent (they don’t know who that is! How adorably out of date and goofy!) and finagle their way into a hopping nightclub where they dance and discover the wonders of Red Bull. Caffeinated old timers? Craaaaazy!

A couple of these kinds of jokes executed cleverly would go a long way, but "Last Vegas" and writer Dan Fogelman ("Crazy, Stupid, Love," last year’s "The Guilt Trip") seem to have nothing else to go on. It’s one joke that gets mighty tiresome after 105 minutes. Pardon me; there’s also a predictable joke involving Sam making friends with some cross dressers, a gag well past its sell-by date. 

The few plot threads and life lessons laced in between all of the tired shenanigans don’t provide many surprises either. Billy starts having second thoughts about his shotgun marriage, especially after meeting a lounge singer, sweetly played by Mary Steenburgen. Of course, Paddy finds himself falling for her too, reawakening their old rivalry and more recent, less friendly feud. It plays out as expected, complete with one character walking into a private conversation at just the wrong time during the film's big, climactic party scene. 

Meanwhile, Sam – with explicit permission from his wife – desperately hunts down a hot young one-night stand with condom and Viagra eagerly in hand. It’s just another well-tread setup for more jokes about a cutely horny old guy that offers few laughs and fewer surprises.

The cast milks this innocuous and breezy material for all its worth. It's mostly a losing battle, but at least they seem to be having fun. Their mere charming screen personalities are almost enough to make even the most lifeless of punch lines almost work. The overqualified vacationing cast, however, works as a double-edged sword because it also makes "Last Vegas" kind of sad.

These were – and when given good, fresh material, are – some of Hollywood’s finest, most charismatic actors. And the film has nothing better to give them than rusty geriatric jokes, slightly condescending them with every scene saying, "Oh, that’s so cute; they still want to have fun."

I’d say it’s depressing that I’ll never be able to watch "Goodfellas" or think about Travis Bickle without also remembering De Niro starring in a movie where a thong-wearing Redfoo repeatedly thrusts his package into the legendary actor’s disapproving face. But that implies that I’ll remember "Last Vegas."