Every few months, the members of one of Hollywood’s exclusive clubs assemble, as they and their predecessors have for the past 68 years, as a way to catch up with old friends and co-workers in a social setting. While they aren’t official business meetings, these folks can’t help but talk shop and swap war stories. Among them, they share more industry credits and awards than Steven Spielberg, Harvey Weinstein and Scott Rudin put together. Yet none are famous faces or boldface names.

In fact, they’re among the most under-the-radar individuals in the industry, despite being among the most important executives at the studios: the heads of physical production. They’re on the front lines of the many battles currently convulsing the film industry: the shift in focus at studios to megabudget franchise and tentpole pictures; the increasing significance of the global marketplace; highly sought-after production incentives; quickly evolving technological advances; and the digital revolution. They touch every live-action film their company makes, and are critical to getting those pictures over the finish line.

The Grog & Chowder Society, as they refer to their club, though not quite a secret organization, is known to few outside their small circle. And they strive to keep it that way, which is why they are loath to talk about it publicly, or privately. “It’s like ‘Fight Club,’ ” says one member, after letting it slip in an interview that the group even existed.

Matthew Hollister for Variety

Between billiards and beers, members shoot the breeze about everything from tax incentives to the latest digital cameras. Convivial as the gathering is, there’s a reason these competitors seek each other’s company — which in itself is a rarity among rivals in a business where studio and network heads don’t typically hang out en masse.

Simply put, these select individuals bond over pressure-cooker jobs that in today’s high-stakes entertainment business are more crucial than ever. They’ve risen through the business in a time of rapid change. They’re ultimate multi-taskers, working on multiple productions at a time (as many as two dozen each), and simultaneously serving as strategists, generals, improvisors, negotiators and go-betweens for the studio brass and the filmmakers and their crews.

“I certainly have relatives who have no idea what I do,” says Paramount Pictures’ president of physical production, Lee Rosenthal. His counterpart at Universal, Jeff LaPlante, says he’s often asked, “So, do you sit on set all day? And what do you actually do while you’re there?”

Even inside the business, their jobs are little understood.

Physical production chiefs themselves define their occupation as a combination of facilitator, planner and problem solver.

Says Rosenthal: “People say, ‘Oh you’re the money guy.’ I think ‘Well, you know, on Wednesday at 9:30, I’m the money guy, or half an hour later I’m the location logistics guy or insurance agent guy. On a really good day, I could be a goodwill ambassador, and most days I feel like I’m a head concierge.”

Their job, in a nutshell, is to oversee the actual making of a movie, from beginning to end. “It’s about delivering to the studio, as cost-effectively as possible, a film that meets or exceeds the (initial) expectations for that film,” says producer Jon Landau, who produces James Cameron’s pictures, including “Titanic” and “Avatar,” and who himself was once head of physical production at Fox.

“On Wednesday at 9:30, I’m the money guy,” says Paramount’s Lee Rosenthal. “Half an hour later, I’m the location logistics guy or insurance agent guy. … Most days I feel like I’m a head concierge.” Photo: Peter Bohler for Variety

Warner Bros.’ Steve Papazian, who with 19 years behind him is the longest-tenured of the physical production chiefs, puts it this way: “It’s like I’m the head of manufacturing. The script is a blueprint, and manufacturing has to engineer it, tool it and figure out how to build it.”

They must be meticulous planners, yet in a crisis, they have to abandon their schemes and ad lib. They may start on a project when it’s still just a pitch, and then stay on it for years until it’s delivered for distribution.

They answer to their studio bosses on one hand, and on the other, serve the project’s creative producers and director at every stage of prep, production and post-production.

Most have risen through the ranks in production, though U’s LaPlante began in production finance. Recalls Lucasfilm’s Jason McGatlin: “When I first started at Warner Bros., to join the union, I had to take a typing test to prove I could be a production coordinator, because they wanted to see how fast you could type memos. They still had the illusion that production was note-keeping secretarial work.”

Fast typing may come in handy for the hours of emails production chiefs face every day, but the job requires an ever-changing array of skills, and knowledge of everything from gun-import regulations in Abu Dhabi to production incentives in Zagreb.

David Grant and Mitch Bell have shepherded the shoots of “Ant-Man” and “Iron Man 3.” Photo: Peter Bohler for Variety

One crucial part of their trade can be summarized in five words: “Keep it in the box.” In fact, it’s nearly impossible to grasp what they do without understanding the box.

Sony’s Andy Davis defines the box as “the financial model, the value of the picture.” Producer Neal Moritz, who has worked with Davis on the “Jump Street” films and with Universal’s LaPlante on the recent “Fast and Furious” pictures, explains that the box has replaced the old progression of script development followed by budget, followed by greenlight.

Says Moritz: “They might like the script, but they don’t want you to give them a budget. They say to you, ‘You’ve got to make it within this box, this budget figure.’ ” It’s then up to the physical production office, working with the producers and creative team, to forge a plan to shoot the film within that framework. If necessary, physical production chiefs might renegotiate deals, and come back to creatives with suggested cuts and changes, from chopping a sequence to a complete reimagining of the script.

“My job is to assist in maintaining the balance of art and commerce,” says Papazian. “Everything we create is art, and art and commerce are a difficult balance.”

The heads of physical production (with their staffs) are expected to be expert enough to project production costs sequence by sequence, yet also to understand story well enough to know which sequences shouldn’t be trimmed, regardless of cost. The most effective production chiefs, says Moritz, will even go back to the studio brass to argue that the picture needs more production funds — that “you might not be happy with the movie you get within that box.”

Once there’s a plan that puts a picture in the box, the physical production heads are expected to keep it there. “The budget is really the actual calculation and outcome of a plan,” says Papazian. “Our job is to keep the film on plan, and therefore keep it on budget.” Going outside the box is like crossing the beams in “Ghostbusters”: bad — with rare exceptions.

That leaves the physical production chiefs walking a fine line. They’re supposed to get the movie onscreen with the filmmakers’ vision intact — but for a price. So they end up being the bad cop, even though none of them see their relationship with the production as adversarial. In fact, smaller cuts may be secretly welcome. Universal’s LaPlante explains that line producers and unit production managers “rely on us to say no to a lot of things. They don’t want to always be the bad guy to the crew members or to the director. So if it doesn’t fit, they can say, ‘The studio’s denied this.’”

Jane Evans got “Delivery Man” back on track for DreamWorks after superstorm Sandy by using the production’s own generators. Photo: Peter Bohler for Variety

Studios’ obsession with sequels, series and franchises hasn’t made physical production planning any easier. Even at Marvel, where films take place in a single cinematic universe, production chief David Grant states flatly: “Every single movie has a different set of logistics that needs to be addressed.” Lucasfilm’s McGatlin echoes the thought: “Every movie, you start over. There’s no efficiency of mass.” It’s a common lament among their cohorts at the majors that nothing happens by rote; planning never becomes routine.

Even a well-established franchise like “Pirates of the Caribbean” was reinvented in the latest installment. Disney had planned to shoot “Dead Men Tell No Tales” in a similar fashion to previous chapters, but Disney’s Philip Steuer — still new to the job at the time — brought to bear some of his experience from shooting “The Chronicles of Narnia: The Voyage of the Dawn Treader.”

“It was a water-based film that we shot entirely on land,” Steuer says. “There is a way to do that now. When the first ‘Pirates’ films were made, you couldn’t really shoot the way we’re shooting this one.” Steuer felt the production needed a place where it could build all 11 of its ships’ decks on land, with experienced crews at hand and an incentive to sweeten the pot. So he guided the shoot away from the Caribbean to Australia, where “Dawn Treader” was shot.

Incentives are top of mind as physical production bosses identify locations, but at times, the execs put visual impact over budget. Moritz hails U’s LaPlante for resisting studio pressure to move second-unit shooting for “Fast 7” from Colorado to Atlanta, where the budget would be helped by Georgia’s subsidies. “Creatively, we didn’t know how to accomplish (key action scenes) in Atlanta with the geography that existed,” Moritz says. “I really credit him with explaining to the higher-ups at the studio that in Colorado, we could get on the screen what we needed.”

Incentives have transformed the industry during his tenure, says Papazian. When he began, 80%-90% of studio movies shot in Los Angeles. Now 90% are filmed elsewhere — and probably half of those are produced offshore, he adds.

But all incentives are not created equal, and the head of physical production must gauge which subsidy most benefits each project. Some reimburse more for expensive stars and director than for crew and digital artists; others favor below-the-line talent and are good for tech-intensive pictures. “What people don’t realize,” says Papazian, “is 70%-80% of the negative cost of a film is labor. I have soundstages and trucks and cameras, all of the tangible assets, but when you add it all up, most of it is human beings. It’s a very labor-intensive industry.”

Warner Bros.’ Steve Papazian oversees production for as many as 60 films at a time, most of which never get made. “A great day for me is to get a film greenlit,” he says. Photo: Peter Bohler for Variety

Besides budget, scheduling and location planning, executives also talk about the importance of “casting” the project with key crew chosen to work well with the director and team. On “Star Wars Episode VII,” Lucasfilm’s McGatlin began compiling lists even before a director and producer were attached to the project. “I had a couple of friends who are a.d.’s and producers in the U.K.,” he says, “and I asked them, ‘If you could make your A-list team, who would that be?’ ” Once J.J. Abrams and executive producer Tommy Harper were onboard, McGatlin could hand them his list of candidates.

Millions of dollars may have been spent up to this point on a project, in development, visual effects tests, script costs and scouting, but a greenlight is far from assured. “If you knew how many we figure out and plan and budget, and just never quite get to the starting line,” Papazian says, ruefully. “So a great day for me is to get a film greenlit. That is a reward after months and months of hard work by an enormous group of talented people.”

After a shoot is under way, the physical production office serves as mission control for the film. Disney’s Steuer says the line producer is “on the ground. He’s a field general. We’re sort of back at the Pentagon.”

That arguably makes the studio the White House, but not all physical production chiefs concur with that analogy. “That implies that the buck stops here, and that our job is to make the ultimate decision, and I actually don’t believe that,” Sony’s Davis says. “I actually think the ultimate decision needs to be made by the filmmakers. If we were making decisions for those people, then we’d never make a good movie.”

Oftentimes, though, it seems that all the forces of nature are trying to squeeze a movie out of the box. That’s when physical production chiefs must be at their most nimble and creative. Superstorm Sandy threw several New York shoots into chaos. DreamWorks’ former head of physical production Jane Evans (who last week departed her post to become a producer at DreamWorks, and was succeeded by Shelly Strong) recalls that just two days after the storm passed, her production, “Delivery Man,” was able to resume shooting even without permits. “The city let us film,” she says. “We used our own generator to light the set, because there was no power, and we had teamsters driving all over the metropolitan area picking up crew because people couldn’t really drive on their own into the city.”

Universal physical production chief Jeff LaPlante began his career in production finance. Photo: Peter Bohler for Variety

Great challenges can come at a micro level as well. Marvel’s Mitch Bell had to swing into action when Robert Downey Jr. injured his ankle during shooting of “Iron Man 3.” Once Downey was tended to, Bell began looking for scenes that could be shot without the star, then conferred with department heads about resuming later on an abbreviated schedule. “In a very short time, you have to make these very large decisions in terms of locations and stages,” says Bell, “and if you’re going to go to a location, you’ve got to push that — it’s a lot of moving pieces that you just have to sit down with everybody and talk through.”

Grant faced more intricate challenges on “Ant-Man,” when director Edgar Wright left the project during pre-production over creative differences with Marvel. A new script would be needed, and would Wright’s designers and storyboard artists stick around? As it happened, all departed but the costume designer, so Grant lined up potential replacements and kept them on hold until new director Peyton Reed could meet with them.

Few challenges surpass that faced by Universal’s LaPlante after the death of Paul Walker during production of “Furious 7.” “We had shot most of the movie with Paul,” LaPlante says, “and we had to figure a way to get the film done, and make sure it would deliver on everything we had hoped for — and honor Paul’s legacy.”

Moritz doubts the film could have been finished without LaPlante’s guidance. “He helped educate everybody else at Universal on what it was going to take,” he says.

With accounting software tracking company-issued charge cards, the production office can monitor spending down to the penny, almost in real time. Says Davis, “It’s rare, if ever, that you get a phone call saying, ‘Today we’re millions of dollars over,’ or even hundreds of thousands of dollars over.” Yet some films do go over budget. Says Moritz: “Because of the financial pressure on movies today, a lot of times the budgets we arrive at aren’t realistic budgets. People will do what they have to do in pre-production to get the movie made, and suffer the consequences when they’re in production.”

It’s up to the physical production chiefs to head off such problems, because satisfactory corrections are difficult — if not impossible — after production starts. “We’re scouts, and we’re meant to smell the smoke,” says Rosenthal. That can mean jumping on a long flight to the set or holding lengthy phone conversations. However they attack the problem, though, they agree that once a picture is going over, getting back inside the box requires a team effort.

“Every movie, you start over,” says Jason McGatlin, who oversees Lucasfilm’s “Star Wars” shoots. “There’s no efficiency of mass.” Photo: Peter Bohler for Variety

Often that means trimming shooting days, but typically, the physical production department has anticipated that possibility by crafting a schedule that can withstand some “horse trading,” as Par’s Rosenthal calls it, where nice-to-have scenes are sacrificed for need-to-haves.

That can be easier to do on a $200 million tentpole with 90-day schedules than on a $10 million picture with a 25-day shoot. As a result, smaller projects are more prone to go over budget due to bad weather or other inevitable snafus. “The hardest part is to fall behind the schedule,” says Papazian. “Catching up is so difficult, and it’s so complex, because everything about a filming schedule is like an intricate puzzle.” Actors and locations, for example, may not be available on later dates.

Adjustments to schedule and budget can go both ways, though. Davis recalls directors Phil Lord and Chris Miller asking for six more days of shooting to expand a particular sequence on “22 Jump Street.” Davis conferred with Sony’s top production executives Doug Belgrad and Hannah Minghella, who agreed that they liked the longer sequence, but not its projected cost. “My team came up with a way to get (Lord and Miller) 90% of what they wanted for less money,” says Davis, who flew to the set in New Orleans to see the directors, and offered this plan B. “They said, ‘We were so nervous that you were coming to yell at us for wanting to spend more money.’ ”

Technology is a constant test for production chiefs, who always have to be up to date on the latest and greatest methods — or, in the case of the next “Star Wars” picture, which is trying to recapture the feel of George Lucas’ original trilogy, on ’70s-style in-camera techniques. More frequently, though, the challenges come in pushing the envelope. Ang Lee is shooting Sony’s “Billy Lynn’s Long Halftime Walk” in 3D at 120 frames per second. Says Davis, “One of the exciting things about the job is we’re doing something that nobody’s ever done before.”

Davis is likely to recount his experiences with high-frame-rate 3D at the next Grog & Chowder meeting, just as his predecessors swapped stories about past innovations, from single-strip color film, telescoping camera cranes and Dolby Digital sound to Cinerama and Sensurround. That’s the enduring nature of their club. Each generation shares its stories with the next, passing on knowledge and experience. “(When) I was an executive in my late 20s at Hollywood Pictures,” recalls Davis, “that was a chance for me to go and see the guys who I thought were the old guys, learn from them, and hear stories. And now I’m one of the old guys.”