“I hope you haven’t gotten to know me well.”

It was an odd goodbye from a man who had just spent 40 minutes talking about his role in Last Vegas, a Strip-based comedy with Robert De Niro, Michael Douglas, and Morgan Freeman.

But that’s Kevin Kline, the cerebral actor who, at 66, is the most unlikely of celebrities to star in a Vegas bachelor-party romp as a guy hitting the Strip for a wild time in the name of celebrating his pal’s first trip down the aisle.

The scenario of Last Vegas, out November 1, is simple enough: As lifelong friends Sam (Kline), Archie (Freeman), and Paddy (De Niro) creak into old age accompanied by the standard senior complaints—health problems, outliving their wives, nonexistent sex lives—their buddy Billy (Douglas) is a lawyer playboy in Malibu whose obvious spray tan and the threads of a man half his age indicate that he has never grown up by settling down. But after spontaneously proposing to a woman half his age, he’s finally getting married. Naturally, the guys must head to Vegas, no fewer than 40 years after their most recent bachelor party.

Kline is often the comedy break in what, despite Hangover comparisons, is at heart a moving story of four men forced to stare down old age and the devastating effects that 60 years can have on friendship. But all of that male bonding happens to occur while they’re reacquainting themselves with the “new” Vegas, with hilarious results. The classics all make it in— hangovers, young women, bar fights, VIP hosts. The men even judge a bikini contest with Vegas regular Redfoo, of the quirky LMFAO. Kline’s character is the guy who hits the pool with old-man socks, a floppy hat, and opaque sunblock on his nose, but the actor insists that aging in Hollywood is more complex than assuming a guy nearing 70 doesn’t know how to look cool at a Vegas pool party. (In real life, Kline is the youngest of the Last Vegas foursome.)

“It’s funny,” he says, “aging in real life and then the professional aging, where you’re suddenly being offered parts where you’re the professor, or the father, or the old friend—they don’t run exactly parallel.”

Maybe not exactly, but Kline does have a somewhat professorial demeanor. He is famously reluctant to talk about himself, but unlike many Hollywood heavy hitters, he doesn’t even like to talk about his work. When put under a microscope, he theorizes. Even seemingly innocuous topics trip up this deep thinker. A question about being in Vegas, for example, yielded several minutes on how an actor on location can’t truly answer that, concluding with, “I can’t say my experience in Africa or Las Vegas or Italy is typical. Is the work going well? If the work’s going well and everybody’s being cooperative, then that makes it a great place.”

If great work makes for a great place, then based on his portfolio, Kline’s passport must be stamped with some pretty amazing locales. His private nature has allowed him the career of a true chameleon. A virtually clean slate, he has never been typecast and has always enjoyed taking on roles with as much diversity as possible. He has been in Hollywood for more than 30 years now, and his movie career spans the swashbuckling musical The Pirates of Penzance, the heavy love story Sophie’s Choice, and the zany comedy A Fish Called Wanda. Later hits include films as varied as the hilarious Dave, in which he played both the president and his look-alike; the drama The Ice Storm, a memorable peek into the swinging ’70s; and the smart comedy The Pink Panther.

“Kevin is the most versatile genius I’ve ever worked with,” says Last Vegas director Jon Turteltaub. “He does heavy, intense drama or slapstick comedy with equal ease, imagination, and confidence. It’s hard to wrap your brain around the fact that it’s the same actor in The Big Chill and A Fish Called Wanda. He changes so much movie to movie.”

Kline’s signature thoroughness and overanalysis aren’t saved for press interviews. Turteltaub laughed when describing his new friend on set: “Kevin never has a really good idea—he has 11. It can be wonderful or a pain in the neck. The 11th idea could be it, but at some point people have to eat lunch.”

Turteltaub had never worked with Kline before Last Vegas, yet the director stayed chatting with him so long the first time they met that his wife had to come break up the party. In fact, while each member of the movie’s Brooklyn-raised “Flatbush Four” is a Hollywood icon, none of the men had ever worked together—or with Turteltaub. (“I was scared to death,” he says.) But they had a good time together during the 11-day shoot in Vegas, where the locations included Aria (the production’s home base), the Strip, Binion’s, even baggage claim at McCarran Airport. Rare nights off yielded dinners at Sirio Ristorante and Jean-Georges Steakhouse, and they saw The Beatles LOVE and O, which Kline calls “spectacular.” In his downtime he frequented Blossom, the Chinese restaurant inside Aria, where he stayed, and relaxed in his suite. Looking back, he admits that the inner workings of our hospitality town impressed him.

“Whenever I called room service, I’d say, ‘I’ll have the chamomile tea,’ and they’d say, ‘Oh, fantastic! Excellent choice!’” Kline says. “‘And an order of toast.’ ‘Oh, spectacular!’ They’re genuinely enthused, very upbeat.”

While the film’s bachelor party devotees hit a loud nightclub and throw a penthouse bash for the books, the actors had very early call times and Kline needed some rest. One evening, that almost didn’t happen.

“There was some party keeping me up,” he says. “I called downstairs, and four people showed up in uniforms with walkie-talkies. They weren’t trained acoustical engineers, but they pinpointed the source of the music, the throbbing noise. It was shaking my windows, and they identified it as across the street and about a mile away and dispatched someone. The efficiency with which they swooped in to deal with that was quite impressive.”

Kline’s lengthy conversations lead one to believe that his wife must be a very patient woman. Phoebe Cates, a 1980s starlet in classics like Fast Times at Ridgemont High and Gremlins, retired from acting in the 1990s to raise their two children—no full-time nanny in this Hollywood household— and help her actor husband when he needs it.

“She comes from a family of producers and grew up going to the theater constantly,” Kline says. “She is really smart. Usually she’s not terribly interested in [acting], but if I really need advice, I will ask her for it, and she will give it.”

In Last Vegas, Kline portrays a socially awkward man who’s been given a free pass for the weekend (and some accessories to help make it happen) by his adoring wife. He hasn’t attempted to pick up chicks in four decades, and, as the actor says, “hilarity ensues.” Retired and bored, in love with his wife but apathetic, his character looks wide-eyed at the anything-is-possible Strip as a way for him to get his mojo back.

Kline wanted to make sure the audience understood that loneliness and would root for the character on his quest for some age-inappropriate tail. “Kevin would make choices here and there, try certain things, and sometimes Turteltaub would say, ‘Okay, great, but don’t do it,’” jokes De Niro. “Or he’d do it. You never know what you’re going to get, but that’s good.”

Freeman, who has known Kline since the 1980s, got a kick out of his approach—even if it meant longer days on set. “I don’t have a problem with actors like Kevin,” he says. “‘How else can I do this? How else can I present this? Can I make this funny? Can I make it funnier?’ That’s the kind of actor he is, and he’s fun.”

As Turteltaub suggested, sometimes it’s hard to believe that certain favorite movie characters over the years were played by Kline. In fact, some fans don’t recognize him at all. They might see an actor who looks vaguely familiar, but they can’t quite place him. And that suits Kline just fine—it’s all part of his strategy.

“I’ve felt since the very beginning of my career that the less people know about me personally, the more advantageous it will be for them if they’re watching me act, the more they can suspend disbelief,” he says. “There are brilliant and successful actors about whom we know intimate details, so some can transcend it. But I just want to stack the deck as much as I can in my favor by being discreet or closemouthed about my personal life.”

Even the turning point of his career, the experience that convinced him that he belonged on stage and in front of a camera, was about the acting, pure and simple. “I took a part on Broadway in On the Twentieth Century, which I first turned down, then got talked into doing it,” he says of the 1978 production. “The part grew in rehearsal, and a song was written for me. We developed it, and the part turned into a really good part, whereas on the page it was not. It got great reviews, and I got a Tony Award. That was when I realized, Well, I’m glad I did this. I almost didn’t. I learned a lot of lessons: how something appears on the page isn’t necessarily how it’s going to end up, that there is a process. That was the moment: ‘I guess I must be doing something right here.’”

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