Co-writers and first-time directors Peter Huyck and Alex Gregory deliver a solidly commercial picture modeled on ’80s summer college comedies. Shot three years ago, the film scored big at this year’s Tribeca Film Festival.

Let’s face it the audience is lured in by the hope of seeing one thing and one thing only. If gratuitous sex is what you came to see then you wont be let down. A Good Old Fashioned Orgy definitely earns its R rating.

A close group of 30-somethings spends every weekend throwing elaborate theme parties at their friend Eric’s (Jason Sudeikis) family home in the Hamptons. When Eric’s dad (played by Don Johnson) informs the group that he intends to sell their beloved Hamptons playground, the friends agree there is only one way to have the biggest and brashest send-off party: a good old-fashioned orgy.

Bringing Orgy to the big screen took 14 years from door to door. Gregory and Huyck began writing the script in 1997 when the Emmy-nominated team was writing for HBO’s “The Larry Sanders Show.”

“The movie came about after we talked to a friend who said he’d been to a party in the hills where an orgy broke out, and we didn’t believe him,” explains Huyck.

It took The 40-Year-Old Virgin and Knocked Up as proven hits before people would take the movie seriously, even though the script was written several years before.

This movie has an extraordinary ensemble cast, including the always-enjoyable Lindsay Sloane (“Weeds,” Horrible Bosses), Nick Kroll (Little Fockers) and Sudeikis’ “SNL” coworker, Will Forte. Kroll, who plays Adam, explains, “I credit Pete and Alex for putting together a cast of people who would be game for an orgy but also becoming very close friends with a group of people.”

“We cast people that we thought we wanted to be friends with,” adds Gregory.

Filming in North Carolina also greatly assisted with the cultivation of real friendships among the cast members, as the actors each lived in small apartments next door to each other in downtown Wilmington.

“We watched the making of The Big Chill and the making of Dazed and Confused, and the cast had really bonded before shooting, it allowed for a certain kind of emotional closeness and bonding that you just can’t fake,” shares Gregory.

When it came to filming the how and the why of the orgy scenes, the filmmakers decided on quite an unorthodox strategy. With most productions, the choice is made to film the sex scenes early on. The rationale being that the relationships are still new and the scenes can be captured prior to any possible tension or passion that might not make the scene play out right. However, in Orgy, they took the opposite approach and filmed the orgy scene on the last few days of production.

This gamble paid off since the friendships formed during the course of filming, not only among the cast but with the directors as well, helped to make what was sure to be a highly awkward work environment a lot less tense. Always the support system, both Gregory and Huyck, along with some members of the crew, helped to put the actors more at ease by shooting the scene in their boxers! Gregory says, “There were also moments when we had to step up and demonstrate our solidarity with the cast, like when they insisted we get our asses ferociously paddled by Lake Bell to experience what we were asking Nick Kroll to endure, take after painful take.” The issue of gender did not influence how the scene played out either. The film made sure to convey that all participants in the orgy were on a level playing field. The semi-nudity isn’t just for the male viewer’s enjoyment.

“A lot of sex-themed comedies play up what we believe is a largely fictitious gender war. We wanted the ladies to be in on the absurdity,” says Gregory.

The actors really committed to their roles, and no body doubles were used. All of the male actors did their own “stunts.”

A Good Old Fashioned Orgy is a raunchy yet hilarious tale of friendship, growing up and moving on with a little bit of sex thrown in for good measure.

A Good Old Fashioned Orgy releases in theaters Sept. 2.