In the murk of a postproduction studio on Broadway, 10 pairs of eyes are riveted to a huge movie screen. Framed in close-up, the actor Spalding Gray is rambling feverishly about the sex shows of Bangkok, his monologue spiced with ribald references to Coke bottles, Ping-Pong balls, bananas and chopsticks. The director, Jonathan Demme, is searching for the proper sound cues to bring out the full impact of what Gray is saying.

"Do we want the thwack when the banana hits the wall?" asks film editor Carol Littleton.

"Let's get rid of the thwack," says the director. "I think we can leave it to the imagination."

All week long, Demme has been sealed inside this windowless cocoon in Manhattan's Brill Building, chain-smoking and guzzling iced tea, injecting hurricane roars, the giggles of Thai prostitutes, whirring helicopter blades, ocean waves, bird cries, crickets, thunder and bits of Laurie Anderson's eerie electronic music into the sound track of Swimming to Cambodia.

"It's just one man, one bare desk—I mean, how odd can you get?" Demme exults. "There's never been another movie like this one. We just make up the rules as we go along."

Which is, in essence, what Demme is all about. From Handle With Care, his quirky comedy about C.B. radio freaks, which played to near empty theaters for a few minutes in 1977, to Swimming to Cambodia, the oddball off-off-Broadway experience now circulating successfully through mainstream America, Demme has consistently made movies that defy Hollywood conventions and reflect his own eclectic tastes and off-sync sense of humor. At the relatively tender age of 43, he is one of a small group of filmmakers—Louis Malle, Bob Rafelson, Martin Scorsese—who brazenly follow their own impulses, shooting shoestring documentaries, rock-concert movies, full-length features and videos, commanding the respect of the Hollywood Bosses yet refusing to be corralled by the studios.

All this is not to suggest that Demme has toiled, until now, in the depths of obscurity. He has long been recognized as a kind of throwback to the late director Preston Sturges, spinning unexpected comedy out of bizarre chance encounters. In Melvin and Howard, which won the National Society of Film Critics award for best picture of 1980, milkman Melvin Dummar gives a lift to a sickly derelict in the Nevada desert and is rewarded with $150 million in Howard Hughes' will. In last year's Something Wild, tax consultant Charlie Driggs is snared in his local greasy spoon by a Louise Brooks look-alike and taken for a joyride turned nightmare through rural America. Demme's characters are yearners and dreamers, groping for fulfillment in trailer parks and Las Vegas wedding chapels, gas stations and truck stops. More than any other director, perhaps, he sees romance and spontaneity just beneath Middle America's surface.

"I could probably be enormously wealthy—taking set-up movies from the major studios," says Demme, sitting in a Times Square bar. He has been divorced since 1980 from director Evelyn Purcell, and now, with his black leather motorcycle vest and unruly shock of brown hair, he has the casual cool look of an NYU film student—a few flecks of gray providing the only hint of incipient middle age. "I've seen what happens to a lot of directors who follow that studio track," he says. "As time goes by, the fire gets lost, the expertise takes over. I'm not like that. I'll listen to any idea, any movie, any budget. If something good can come of it, I'll dive right in."

All of this represents a surprising turn of events for an erstwhile veterinary student who might well be pulling kidney stones out of dachshunds today if he hadn't flunked college chemistry. Demme was raised on Long Island and in Miami, where, he says, "My mother had a friend who was a vet—he let me come in and swab down his tables, disinfect things, change the water. I was in paradise."

But Demme also loved movies and eventually took a part-time job as a movie reviewer for the Independent Florida Alligator. That led to a job in Miami churning out criticism for a shopper's throwaway. Then—in one of those life-transforming encounters that might be known as the Demme motif—his father, Robert, then head publicist for the Fontainebleau in Miami Beach, introduced him to the producer Joseph E. Levine, who docked his houseboat across the street from the hotel.

"He opens my scrapbook, he's thumbing through the reviews, and he gets to Zulu, which was one of his pictures," says Demme. "I had written a rave, and he goes, 'Ya like Zulu? Ya got great taste, kid. Ya wanna come work for me?' I said, 'Sure, I'd love to.' 'So where do ya wanna go? New York, London or Rome? I got offices in all three places.' "

A press agent's job in New York led next to London, where Demme worked as a sales representative for an American commercial production company and doubled as rock correspondent for the Boston-based weekly Fusion. "I was smoking a lot of hash," he says. "For a while that was my favorite thing in life." A few years later, a publicist's job opened up on the set of a Roger Corman movie filming in Ireland, where Demme's enthusiasm and B-movie knowledgeability brought him to the producer's attention. "Roger said, 'Now lemme ask you something—Do you like motorcycle movies? Okay, here's my problem: I just started New World Pictures. I want to produce 10 pictures this year, but I only got three scripts. You're an American. You love movies. Do you wanna write a motorcycle script for me?' I said, 'Sure.' "

Demme teamed up with his buddy Joe Viola (now a writer on Cagney and Lacey) to write Angels Hard as They Come, a biker adaptation of Rashomon. Next came Hot Box, a nurses-in-bondage picture shot in the Philippines amid typhoons, political bombings and, ultimately, Marcos-imposed martial law. "I was 26 and unmotivated," says Demme, "and here I was screenwriting, producing, making movies. I began directing second-unit stuff, and I fell in love with it. I thought, 'This is really fun!' "

Corman gave him his first directing assignment in 1974: Caged Heat, a $180,000 cheapie about a female prison-farm jailbreak. It is best seen on cable in the small hours of the morning, but for Demme it constituted a breakthrough. "Corman took me out to lunch when I was about to direct my first movie, and he spelled out a bunch of rules that I've never forgotten. The first was, 'You can't look down on your characters. You've got to make the audience care about them.' He also pointed out that when you make a movie you have to keep the eye stimulated. That meant well-motivated camera movement, editing at the right time, quality action in the foreground and background. You lose the eye, you lose the brain."

He did two more Bs for Corman, Crazy Mama and Fighting Mad, before landing Handle With Care in 1977. This weirdly funny movie about a bunch of putatively normal but thoroughly cracked Midwestern eccentrics linked by their citizen's band radios delighted critics and cultists, yet bombed so badly that Demme was literally unemployable in Hollywood for almost a year. ("I was begging for a game show—anything!" he says.) Then appeared Melvin and Howard, which came to him on the bounce when Mike Nichols turned it down. The film won Academy Awards for actress Mary Steenburgen and screenwriter Bo Goldman, giving Demme a second lease on life as a Golden Boy. Yet he found himself increasingly embroiled in confrontations with studio moneymen over scripts, casting—every aspect of the creative process. In fact, he had disagreed vigorously with Universal over Melvin and Howard. One point of contention concerned who would play Melvin Dummar (the studio wanted Gary Busey; Demme demanded—and got—Paul Le Mat) and Howard Hughes (he wanted Roberts Blossom; the studio demanded—and got—Jason Robards).

Later an even angrier dispute was waged over Swing Shift, which Demme saw as the story of a developing friendship between two women (Goldie Hawn and Christine Lahti) who meet in an aircraft factory during World War II. After the movie was in the can, Warner Bros, and Hawn, who was executive producer, insisted that Demme re-shoot to downplay the female bonding and emphasize Goldie's romance in the film with Kurt Russell. Thirty-five pages of rewrites later, Demme walked out for good. "Swing Shift really took the wind out of my sails," he says. "I was, in Spalding Gray's words, 'in a slough of despond.' Now, with Stop Making Sense [the Talking Heads' immensely successful 1984 rock concert film] and Something Wild, the wind is back up."

Indeed, Demme's freewheeling style is displayed at its most uninhibited in Something Wild. Filming last year in Tallahassee, Fla., Demme spent hours prowling the surrounding neighborhoods, searching for snippets of raw local color that would give the picture its special gamy vitality. Noticing a group of rap musicians performing outside a gas station, he had them on camera in a matter of hours. A mesmerizing reggae singer, Sister Carol East, was signed up after Demme caught her act in a New York nightclub. Still others—break dancers, street performers, even oddball pedestrians—were hired on the spot and brought in as part of the rich background sideshow. The result was a unique hybrid: part screwball farce, part suspense thriller, part joyous celebration of eccentric diversity.

"Jonathan listens to any idea, no matter how idiotic. And he tries a lot of them, because sometimes they work," says Jeff Daniels, who co-starred in Something Wild with Melanie Griffith. "I might turn around and see this dog on a motorcycle or a black hitchhiker wearing a cowboy hat. You know you're walking through a Jonathan Demme movie because of the things he puts behind you and around you. There's an improvisational feeling to everything he does."

It is lunchtime in midtown Manhattan, and Demme is bustling down Broadway, his rainbow-striped African scarf flapping in the breeze, his arms spilling over with Haitian paintings, reggae albums, notebooks filled with jottings and Demme penseé's. In his high school baseball jacket, baggy khakis and tennis sneakers, he looks like a prophet of New York Hip, cruising to the ganja-inspired rhythms of ghetto blasters and record-store loudspeakers. Soon Demme would be flying to Haiti with fellow filmmaker Jo Menell to shoot a television documentary, on a nickel-and-dime budget, commemorating the first anniversary of Baby Doc's overthrow. Inspired by the setting, he has since filled his office with Caribbean sights and sounds.

A pink, purple-fringed Haitian beachcomber's hut looms in the hallway, hammered together out of plywood—for "artistic inspiration," Demme says. Jimmy Cliff music pulsates throughout the office. The place is awash with primitive art canvases, a well-thumbed copy of Let's Learn Creole, a gourd-shaped piece of granite that he calls a thunderstone—blessed, according to Demme, with supernatural properties conferred by Caribbean deities.

Blessed, in fact, is just how he feels. "I went through a couple of years after Melvin and Howard where all I did was develop scripts, and none of them ever made it off the ground," Demme says. "I feel like I'm shooting all the time now. Of course, my favorite thing to shoot is a feature film. You go to war—in the sense that your life falls by the wayside. It's a sustained rush. You're interacting with so many people, it's fantastic."

Still, for all of Demme's projects, his exhilaration, his manic bursts of activity, a sense of discontent hangs about him. After 15 years as a moviemaker, Demme has yet to find the work that will bring him mass popular acclaim. He looks upon fellow directors such as James (Terms of Endearment) Brooks, Oliver (Platoon) Stone and Barry (Diner) Levinson with mingled admiration and wistfulness, because they have all had the breakthrough—the unexpected, unconventional film that succeeded beyond anyone's dreams. Jonathan Demme would like nothing more, at this point, than to have one of those sublime accidents happen to him. "I'm still waiting," he admits, "for my Terms of Endearment."