Mark Wahlberg, Denzel Washington have fun in '2 Guns'

In summer, a young moviegoer's mind turns to thoughts of sequels. So what happens next year if the Denzel Washington-Mark Wahlberg buddy movie "2 Guns" is a bona fide box-office blockbuster?

"3 Guns"? "4 Guns"? "5 Guns"?

"I have no idea," director Baltasar Kormakur replied with a laugh. "I have no idea how any of this will turn out, but we could have fun with it -- '2 Guns 2'? '2 Guns 3'? I really don't want to think about it."

Not yet, anyway: Opening Friday, "2 Guns" stars Wahlberg and Washington as a DEA agent and a naval intelligence officer, respectively, who are investigating each other, in the belief that each is stealing money from the mob. When they discover they've been set up -- and have inadvertently ripped off the CIA -- they have to find a way to return the money.

Even Kormakur -- a one-man movie industry in Iceland, and probably his country's best-known filmmaker -- said it's not important to take the story too seriously.

"The story is not what you remember at the end of the day," he said. "It's the characters and the relationship and enjoying being with them."

Which may make "2 Guns," based on the graphic novel by Steven Grant, with a screenplay by Blake Masters, harder to categorize than most summer releases. The director said he was striving for a "masculine but lighthearted movie in the vein of 'Butch Cassidy and the Sundance Kid,' those kind of movies, which don't take themselves too seriously but have fun. That was the tone I was trying to find."

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And Wahlberg thought he could find it. Already attached to the project, he brought Kormakur on, suspecting his Icelandic friend was the guy who could find the groove for a movie that's neither a full-blown comedy nor a totally action-driven thriller.

He and Kormakur had already worked together on "Contraband" (2012), which was not only a remake of an Icelandic movie, but one in which Wahlberg was playing a character originally portrayed by Kormakur.

"That was the elephant in the room for me," Wahlberg said. "Was he going to expect me to play it the way he'd played it? But I loved working with him. He never shortchanges himself or the movie or you; late at night, he keeps going till he gets it right. And at that point I have a big smile on my face. And he's great with actors. He wants people to bring stuff to the table."

This included Washington, who is not exactly known as Mr. Mirthful. "But every dramatic actor with good timing for me is capable of comedy," said Kormakur. "Comedy is timing, anyway. If you have that, you can do it."

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And it makes it more interesting, he said, to have an actor stepping out of his comfort zone. "It makes it fresh for me," he said. "Like when Robert De Niro was in 'Midnight Run,' I was like, 'Wow, he's funny.' Up till then, I'd just seen him slaughter people."

Wahlberg said it only made sense to make the film if they could make something different and interesting, with the right people. "And who better for me to work with than one of the greatest living actors?" he said of Washington.

For his part, Wahlberg said, "I love a challenge and especially something that can end up being better than its potential. My people have been trying to steer me toward comedy, and I've been doing a lot of it -- not pratfalls and stuff, just trying to play it real, comedy that comes out of a situation. Something grounded, and working with somebody like Denzel. He got very comfortable with trying stuff out, and once that happened, it was game on."

Kormakur said it was important not only for the movie to have the right sensibility, but to set the audience up for what they're getting. "If people expect comedy, they put themselves in a different mode," he said. "And they're kind of not expecting to be laughing at Denzel Washington. So that's what I was trying to do."

He agreed that the movie might skew toward older audiences. "But it's also testing really well with women," he said. Of course: Wahlberg and Washington. What's not to like?

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"Yes, but I think it has to do with the relationship," the director said. "It has a heart, it's not cold, it's a warm movie, and the action doesn't take over and become too noisy and loud."

In other words, it's not like a standard summer movie.

He's been on the mark

Having pretty much erased his hip-hop and underwear origins, Mark Wahlberg has emerged as one of the more reliable actors of his generation, and maybe one of the more underappreciated:

"Ted" may not have done everything for him it should, and Christian Bale hammed him off Oscar's radar in "The Fighter," but there have been some very fine performances, among them:

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BOOGIE NIGHTS (1997) -- As the centerpiece of Paul Thomas Anderson's genius drama about the '70s-'80s porn business in California, Wahlberg was a marvel of innocence and eroticism as Eddie Adams, aka Dirk Diggler, the superstar of studliness.

THE DEPARTED (2006) -- Considering the level of villainy being generated by Jack Nicholson, Matt Damon and Ray Winstone in Martin Scorsese's Whitey Bulger homage, Wahlberg made himself particularly loathsome as the pugnacious, bilious and generally dislikable Det. Dignam, who is actually a good guy, even though you hate him.

SHOOTER (2007) -- A more typical Wahlberg vehicle, perhaps -- his assassin on the run is framed for trying to kill the president -- but also the kind of movie you can tune into at any point, anywhere, anytime it plays on TNT, which seems to be every other day.

THE LOVELY BONES (2009) -- It's an odd creature, this Peter Jackson-directed adaptation of the best-selling Alice Sebold novel. But Wahlberg was genuinely moving as the heartbroken father of the murdered Susie Salmon (Saoirse Ronan), who is telling her story from beyond the grave.

THE FIGHTER (2011) -- The most genuine performance delivered in this Academy Award-winning film by David O. Russell was by Wahlberg as boxer "Irish" Mickey Ward, who is going back into the ring carrying his useless family on his back. Wahlberg got a nomination, but the Oscars, of course, went to Bale and Melissa Leo, for most successfully sucking the air out of the room.