The thing that makes “Neighbors” different from most frat house comedies is that it's about coming to grips with growing up and moving on.

In the most developmentally arrested way possible, of course, but that's still a step beyond the old-school Animal House. Anyway, it got us wondering what “Neighbors' ” stars, Zac Efron and Seth Rogen, thought about all that maturing business — which is catching up with the onetime youth icons mighty fast.

“Yeah, I'm coming into a new level of maturity, it seems like, every day,” says Efron, 26, the heartthrob from Disney Channel's hit “High School Musical” movies who, besides making the usual Mouse kid effort to establish an adult acting career, has recently undergone substance abuse rehab and was involved in a violent confrontation with a homeless man in downtown L.A.

 

“I'm probably more mature than I'd like to be at this point,” semi-ruefully reckons Rogen, 32, long a mainstay of outrageous sex and stoner comedies (“Knocked Up,” “Superbad,” “Pineapple Express”). “I just now have a job that puts me in charge of gigantic amounts of money at times. From that, we kind of have a lot of responsibility.

“There are many times when I'd like to do much less than I'm doing,” Rogen continues. “That said, I really appreciate my job and how great it is that I get to do what I get to do. So, overall, it's First World problems, as they say.”

 

Rogen, who also co-produced “Neighbors,” plays Mac Radner, the parent of an adorable baby girl with his wife Kelly (Rose Byrne) and a gainfully employed new homeowner. Loving and responsible family folks though they are, the Radners really would like to indulge some of their old, freely partying ways — if they just had the time and energy to do so.

When Delta Psi Beta moves into the Craftsman next door, the Radners are initially stoked to have a 24-hour rave available just a few feet away. Nice for a night, but when the Radners go too far to get the fraternity to quiet down for an hour, a truly disturbing prank war escalates.

 

Efron plays Delta Psi's president, Teddy Sanders, whose devotion to the Dionysian Greek lifestyle is matched only by his terror of what life after graduation may hold. That may make him and Mac antagonists, but another one of the movie's sly subterfuges is that neither guy is particularly sympathetic nor unjustified.

And they both do some pretty awful things.

“For me, it was trying to find out what drives Teddy to be so extreme,” Efron explains. “What could make a person do and say such heinous things, and where could it come from that was an honest place?

 

“Luckily, I realized pretty quickly that I have some close friends who are kind of like Teddy,” Efron reveals. “Not to a T, but there are variations of several different friends, qualities about them that I was able to define Teddy with. I knew that a couple of my best friends are considered, by other people, douche bags. But I also know that those friends would take a bullet for me and I know what makes them great people.”

Rogen points out that underlying emotional issues drive each camp's appalling actions.

 

“The fear of growing up was the real common thread between all of the characters,” he says. “When we make a comedy, we really like for there to be some kind of emotional idea that we relate to a lot. That's what, maybe, makes this slightly more resonant and well-rounded than you would expect a movie with this many dildo jokes to be.”

Growing up has its drawbacks. Because of an adult situation — director Nicholas Stoller's (“Forgetting Sarah Marshall”) pregnant wife was on bed rest during production — the film was shot primarily in Los Angeles' West Adams district without benefit of any state tax incentives, which have become vital elements of most major films' cost controls.

 

“I can say we had to spend a third more of the budget's money than we would have wanted to just to shoot in Los Angeles,” producer Rogen notes. “L.A. really makes it difficult, financially, to film there. The crews are really good, though, so that makes up for it in some ways. But (L.A.) doesn't make it easy for you, by any means.”

At least pretending to party like the frat boys they never were must have been a cool distraction, right?

“Not really,” Efron confesses.

“It seems hard,” Rogen adds. “It seems like a lot of commitment, work and effort just to get drunk.”

 

“I appreciated the chance to go back and fully immerse myself in the lifestyle for a number of weeks, and then never have to do it again,” Efron continues. “It was a fun trip. I've always been curious, so I kind of got to see what it may have been like.”

For Efron, who's been making a concerted effort to live a healthy, sober life, hanging around pothead poster boy Rogen for all that time did not have the effect one might think.

“I'm very encouraging,” Rogen says with an ironic laugh.

“No matter what's going on, we always have a good time,” Efron affirms. “One thing I actually learned from Seth was a lot of, like, work ethic. I've always put everything I have into my work, but I think Seth showed me a whole new stratosphere of what you can do on set to make your time valuable.

 

“I learned a lot about what it means to act in and produce a film at the same time,” adds Efron, who executive produced his comedy “That Awkward Moment,” which came out earlier this year. “Like, Seth was never in his trailer or off set. Now, I hope to be a more valuable player on set after watching Seth work.”



Follow Bob Strauss on Twitter: @bscritic