By Scott Bowles
LAS VEGAS - Ed Helms hoists a massive wooden mallet over his head and stares at Bradley Cooper as if he's going to bash the guy's brains in.
"What is that?" a grinning Cooper asks as he and Zach Galifianakis settle into a corner table at the Nobu restaurant at Caesars Palace.
"It's the hammer of Nobu!" Helms says of the decorative prop he swiped from a bin. "I believe I'm supposed to bludgeon you with it."
Cooper shoots him a mock-stern look. Helms offers a mock-sheepish face and puts the mallet down.
The Wolfpack isn't all about clowning around.
Certainly, goofball behavior molded the Hangoverseries into the highest-grossing R-rated comedy franchise in history - with just two movies. And it will be the stirrer that mixes The Hangover Part III(opening Thursday), the final installment of the saga of the Wolfpack, the hapless trio whose Vegas visits are as subtle as a Mike Tyson sock to the jaw.
But get the comedians together in a room without cameras, fans or onlookers, and they can get downright sincere. To the last man they will say it's not antics that propel Hangover movies. It's affection.
"Great actors can fake chemistry," Cooper says. "But audiences know when it's really there, and I think that's what people pick up on. We really are friends, off the set as well. If you have that warmth for each other, you get it back from fans."
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Audiences have been giving plenty back since the franchise launched in 2009: More than $1 billion in box office worldwide, including $532 million from blissfully hung-over U.S. moviegoers. The original film became the biggest R-rated comedy of all time and the third-biggest R-rated film overall, with $277 million. The Hangover Part II took fourth on the all-time list of R movies, with $255 million.
That leaves a lot riding on the latest outing this Memorial Day weekend, Hollywood's most important outside of Thanksgiving. Hangover III will face the first blockbuster showdown of summer as it competes with Fast & Furious 6 and the animated fantasyEpic.
If the Wolfpack - the moniker our hard-drinking characters gave themselves four years ago - is nervous about the stiff competition, it takes a backseat to the trio's bigger priority: staying in touch after the film opens.
"This is a nomadic industry, and you say you'll stay close with people you won't see again for years," says Helms, 39. "But we went through a roller-coaster ride together with these movies, and we became actual friends, no cliche. That doesn't happen often, and you don't want to let it go when it does."
When the three auditioned in 2008, the comedians knew each other as colleagues who would catch an act or bump into each other at premieres.
They exchanged obligatory "we gotta do a movie sometime" niceties, but it wasn't until an informal table-read in West Los Angeles with director Todd Phillips that the three noticed a spark.
So did Phillips, who auditioned his actors as a group to measure their chemistry.
Not that he calls it that.
"I call it anti-chemistry," says Phillips, who directed the ensemble comedies Road Tripin 2000 and Old School in 2003.
The key, Phillips says, "is finding guys who don't appear to be like each other. Too many comedies have actors whose comedy styles are similar, so it's one note. I like guys whose styles are polar opposites of each other."
Cooper's Phil would be the cocky ringleader, a partier who enjoys company at his benders. Helms' Stu became the straight man who tends to get tattooed or toothless when he joins said bender.
And Galifianakis' Alan provided the outlandish humor, a role he reprised regularly off set, Phillips says.
"Basically, every Hangover movie has been me and Zach, trying to make each other laugh when the cameras aren't rolling," he says. "Then we put that in the movie."
Those barb sessions would make up the backbone of the first Hangover, whose original plot did not include what would become iconic gags of the series: a tiger that appears in their Vegas bathroom; a punch from Mike Tyson using Galifianakis' face as a flesh drum to keep rhythm to Phil Collins' In The Air Tonight; an abandoned baby strapped perilously to Galifianakis' belly.
"The structure of the film was there before Todd came on, but it wasn't as imaginative," Helms says of the original script. "But when we all came on, all bets were off. There wasn't a scene we wouldn't try."
Though there were scenarios they nearly couldn't pull off, including the emergency room setting in which the actors said they formed their tightest bond.
The scene, which called for the Wolfpack (and baby) to watch an elderly man drop his drawers, took more than a dozen takes as the actors kept cracking up. "I'm not sure how we ever got through it," says Cooper, 38. "But we were in hysterics. We knew we got each other."
They get in deeper water than ever the third time around, as they try to track down the unscrupulous drug dealer Mr. Chow (Ken Jeong) and face an international assassin in John Goodman.
But the approach to the franchise remained the same, Phillips says. "You set up a camera and let them be the Wolfpack, because they're kind of a real one, with as much heart."
Occasionally to the (unintentional) exclusion of co-stars, Cooper concedes.
"I love everyone we work with, but it's different," he says. "I don't think I've ever felt as natural in a group as I am with those two. I can just turn my brain off and be myself."
Cooper pauses and gets more serious. When his father died of cancer in 2011, "Zach was the first person I called," he says. "We went from co-workers to friends a long time ago."
"People like us to act like the characters in the movie, and I get that," adds Galifianakis, 43. "But that really isn't our personality, other than enjoying hanging out together."
Not that the group won't party during the farewell. The trio will hit an international circuit of premieres in London, Paris and Rio.
"That's when we'll get to say our goodbyes, at least on these movies," Galifianakis. "Rio could be wild."
Helms chimes in: "If we don't break down sobbing."