Amy Miles speaks in a soothing Southern accent, is quick to flash a smile and, when the mood strikes, offers up a loud, disarming laugh. The Regal Entertainment Group chief exec cultivates an informal atmosphere at the firm’s nondescript corporate headquarters in Knoxville, Tenn. Instead of using the intercom to chat with chief operating officer Gregory Dunn, she often shouts back and forth with her deputy from her adjoining office.

But despite her affability, the 47-year-old Miles is a shrewd operator, tasked with overseeing the world’s largest theater chain, comprising 7,349 screens across 574 theaters. Not only is she one of the most influential figures in entertainment, she is one of only two women — with National Amusements’ Shari Redstone — currently heading a major circuit.

The National Assn. of Theatre Owners, the exhibition industry’s lobbying arm, has relied increasingly on Miles to be one of its most important messengers. “It’s important to have women in leading positions in this business,” says NATO president John Fithian, “because women buy most of our tickets every year.”

Studio executives describe Miles as a force to be reckoned with. “She’s a tough negotiator,” says Rory Bruer, head of worldwide distribution at Sony Pictures. “I would not suggest anybody try to get something past her.”

For instance, when Netflix and the Weinstein Co. announced late last month that they would release a sequel to “Crouching Tiger, Hidden Dragon” online and in select Imax theaters simultaneously, Regal joined AMC, Cinemark and Carmike in declaring a boycott of the film.

Along with her shrewd negotiating skills, Miles is known for helping engineer the exhibition industry’s conversion to digital cinema. But the Regal chief will need to stay vigilant as change and severe challenges confront the theater business. Like all exhibitors, Regal must keep moviegoing fresh to survive in an era where Netflix, smartphones and videogames represent an existential threat.

“I have to keep thinking about ways to make you get off your couch and come to my location,” says Miles, a former accountant who has run Regal since 2009. “We have to keep improving our asset base.”

To that end, Regal is investing in infrastructure, installing luxury seating across 300 screens this year, and has begun serving alcohol in 30 theaters. The chain is trying out new concessions, expanding its offerings to include finger foods.

This year has been a bruising one for the theatrical business. The summer domestic B.O. plunged 15% to its worst numbers since 1997, when adjusted for inflation. Year-to-date ticket receipts Stateside are down 5.3%, and attendance is off 5.7%. Still the Regal chief says she views the downturn as an aberration. In particular, she’s excited for 2015 and 2016, which bring sequels to James Bond, “Star Wars,” “Superman” and “The Avengers.”

“If you go back 30 years, it’s been peaks and valleys,” Miles says. “The good news is, we’ve worked ourselves up to higher peaks and higher valleys.”

Greg Miller for Variety

Regal has not been immune to the box office doldrums. In its most recent quarter, the company missed Wall Street’s projections, with revenue falling more than 8% to $770 million. Net income dipped modestly.

For now, exhibition industry chiefs keep repeating that next year will be brighter. Investors seem to be buying that argument. Regal’s share price has stayed north of $20 throughout the summer, but should ticket sales remain in a slump, these companies could be looking at something far starker than a seasonal dip.

Analysts and exhibition execs maintain that 2015 could be a record-breaker — which creates an opportune time for consolidation. Some movie theater owners may not want to invest in upgrading their facilities, and the prospect of two strong years of box office growth make this an appealing time to sell.

That’s good news for an aggressive acquisitor like Regal. Under Miles, the company has made deals for the likes of Hollywood and Signature theaters and Hoyts Cinemas. With a $3.18 billion market cap and $355 million in cash on its balance sheet, Regal is well positioned to keep buying. Miles estimates there are between 2,500 to 3,000 U.S. screens that would make attractive acquisition targets if they went on the block.

Media analysts praise Miles’ stewardship of Regal, commending her for being expansionist and fiscally prudent. “Even as the largest exhibitor in the industry, they’re still looking for ways to tweak the model to enhance revenue,” says analyst Marla Backer.

Miles caters to different constituencies, but being based in an office park in Tennessee’s third largest city, Regal is geographically removed from the centers of finance and filmmaking. “My team that negotiates with the studios,” she says. “They’re all here. They’re not playing golf on Fridays or Saturdays with studio heads. We’ve kept that distance, which is healthy.”

Knoxville is also the city where Miles grew up, met her husband, Dan, went to college at the nearby U. of Tennessee, and remained to raise two sons, both now grown. Dan stayed home to look after the boys after Amy was appointed chief financial officer at Regal in 2000. Her father, a contractor, built her house, and she regularly socializes with both of her sisters, who live in Knoxville.

Growing up, Miles went to the movies nearly every Saturday, and she still considers herself a frequent ticket-buyer.

“Studios always go after that fanboy,” Miles notes. “I could fit right there with them. I don’t catch opening weekends like I used to with my boys, but when I look back at my moviegoing in any year, what tops the box office is what I go to.”

Regional roots aren’t the only thing separating Miles from her fellow captains of exhibition. She is a woman in a male-dominated industry.

“I hope it’s changing,” Miles says about the lack of gender diversity. “We all serve a customer base that’s not just a bunch of older white males. For us to have a good perspective on our base, we need diversity of gender, diversity of color and a diversity of perspective.”

Studio executives praise Miles for her professionalism, but they have clashed in the past. Perhaps no fight was more bruising than the one that erupted in 2011 over plans by Warners, Sony, Universal and 20th Century Fox to offer films via video-on-demand 60 days after their theatrical release. Typically, studios wait to make films available on home entertainment platforms until 90 days after they debut.

Though Regal was one of the chains that came out forcefully against attempts to shrink windows, studio insiders say Miles handled the situation diplomatically. “She’s always level headed,” says Dan Fellman, president of domestic distribution at Warner Bros. “Exhibitors are our partners in this business, but when issues come up, some get a little more overheated than others. Not Amy.”

Fithian thinks Miles’ background as an accountant for PricewaterhouseCoopers, where she spent a decade before joining Regal in 1999, keeps her from making any dust-up personal. “Amy keeps it very professional,” he says.

The studios ultimately backed away from the windows brinkmanship, but privately many executives expect that the issue will be revisited. As far as Miles is concerned, fiddling with home entertainment release dates could wreak havoc. “That’s a slippery slope,” she says. “Does a consumer’s perception that a movie’s going to be in my house sooner lower the overall box office pot? That’s my concern.”

Earlier this summer, Miles told investors and analysts that when the box office is booming, it strengthens ties between studios and exhibitors. But with ticket sales waning, are things still rosy?

“The anticipation of good box office is carrying the day,” Miles says. “Over time, that symbiotic relationship — I need movies, they need movie theaters — keeps things stable.”