Is John Hamburg the new Judd Apatow?

It has become something of a given that today’s comedies will revolve around the inability of men to face the responsibilities of adulthood and simply act like grown-ups. And while these comedies pull in plenty of laughs with their gross-out humor and joking interplay between man-boys, there is little getting under the hood of how grown men navigate relationships between one another.

In “I Love You, Man,” which opens today, director and co-writer John Hamburg set out to buck that trend by writing about a responsible guy with a good career who has problems of a different sort. Which is not to say the film does not still find its way into a boys-only world by including rock power-trio Rush -- an ultimate guy’s band. Hamburg also nods to the lineage of buddy comedies by casting Jon Favreau, in an allusion to “Swingers,” as an outrageously peeved husband.

In the film, Paul Rudd plays a Los Angeles real estate agent who, after proposing to his girlfriend (Rashida Jones) and pondering who his best man will be, realizes he has too few male friends in his life. None, actually. So he sets out to make some and winds up with a slacker-ish guy’s guy played by Jason Segel. As the two men fall into a fast friendship, Rudd finds his relationship with his fiancée tested and all boundaries between life, work and romance crossed.

“I like awkwardness in movies,” Hamburg said over an egg sandwich breakfast in Los Angeles just before leaving for the recent screening of “I Love You, Man” as the opening-night film of the South by Southwest Film Conference and Festival in Austin, Texas, where it got a big response.

“I feel like male friendship is just so replete with awkwardness because men don’t really describe how they feel,” he said. “There’s all sorts of things they want to say that I don’t think they say to each other because they hide behind a facade of stoicism, that sort of macho behavior.

“And I thought it would be interesting to explore that deeply, with no villains or bad guys. It’s just the story of two people coming together in a relationship where there’s really no rules. There is no ‘Wait two days to call’ or any of the things that have been set out in romantic comedies. There’s no guidebook.”

In its own sweet-natured way, the film gives some idea of just what the “Guy’s Guide to Friendship” might look like, as it includes discussion of discreet farting techniques, the parameters of acceptable masturbation fantasies and the protocols for what constitutes a standard “man date.” In cracking the code for dude-on-dude bonding, Hamburg just may have turned “I Love You, Man” into, as Esquire magazine recently called it, “The Last Buddy Comedy.”

Hamburg, 38, debuted as the writer-director of the 1998 cult comedy “Safe Men,” which featured a then-largely unknown cast that now reads like an enviable ensemble, including Mark Ruffalo, Paul Giamatti, Sam Rockwell and Steve Zahn. He hit major success as a screenwriter with his work on “Meet the Parents” and “Zoolander,” and wrote and directed the 2004 comedy “Along Came Polly.”

“I Love You, Man” began as a script by Larry Levin about a guy engaged to be married who needs to make some male friends fast. The project attracted interest from a raft of writers and directors including Hamburg but never came to fruition. The idea would nevertheless stick in Hamburg’s mind and he would eventually write his own version of the story. (The screenplay for “Man” is credited to Hamburg and Levin, from a story by Levin.)

“What appealed to me was hitting male friendship just head-on,” said Hamburg of what brought him back to the concept. “I like the idea of putting that front and center.”

Producer Donald De Line said Hamburg was just the guy to make it happen, which is why he pursued him over several years to take on the project. “He writes characters that are real, they have off-center, strange bits and pieces to them, as people do in real life,” De Line said. “John just has a great ear; he gets funny little behavioral gestures and moments that pepper the piece from beginning to end.”

All while coming at men’s relationships from a new perspective.

“There’s a lot of movies about a man-child becoming an adult,” Hamburg said. “That’s a very common through-line in contemporary comedy. And I’ve probably written my fair share of that kind of thing. But I liked the idea of a guy who’s actually grown-up, a very evolved man -- he’s a great boyfriend, he’s got a good career, he’s responsible. He almost has to go the other way, tap into a part of himself that most of us learned in middle school or high school, just hanging out with friends and doing stupid things.

“It’s like my ‘Benjamin Button.’ ”

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