CEDAR FALLS, IOWA -- We have only the author's word that it happened this way, but ...

On Friday the 13th in July 1990, Robert James Waller -- at the time a 50-year-old economics professor and sometime folk musician -- was on his way home to Cedar Falls after a day of photographing the old covered bridges of Madison County, southwest of Des Moines. Driving through the midsummer heat, Waller began to hear a line from a song he'd been working on recently, "an old bossa nova tune" about a woman named Francesca.

Waller got to wondering about her. What if Francesca lived in Iowa? And what if she met a man, a man named -- Robert? Robert Kincaid. And he was a -- Waller looked at his camera bag on the seat next to him -- a photographer! Suddenly it began to come so fast that Waller grew agitated and had to stop at a small wayside park and scramble out of his truck.

"I got down and just started walking around and around," says Waller, "and I had this feeling of something about to happen that was so intense. I thought I was going to explode."

At home, Waller went straight upstairs, to the cramped corner of the loft where he works, and began to write what would become, by early 1993, the best-selling book in the United States. He says he didn't stop, except to eat and sleep, for 14 days. "I never wanted it to end," he says.

When he finished, Waller had completed a spare but emotional short novel called "The Bridges of Madison County," about a 45-year-old Iowa farm wife and her four-day affair with a 52-year-old photographer from National Geographic. Despite their brief time together, Francesca and Robert fall into a transcendent, slow-moving spiral of courtship, love and mutual seduction. Then they part, never to see each other again. As an afterthought that would haunt him in small ways later, Waller added a prologue and an epilogue setting the book up as a true story that was told to him many years after the fact by Francesca's children.

With help from friends, Waller secured an agent in New York. Presently, "The Bridges of Madison County" was sold to Warner Books, and the film rights were optioned to Steven Spielberg. An initial printing of 29,000 copies arrived in bookstores last April.

At first it sold slowly. But then smaller, independent booksellers across the country fell in love with the book and began urging their customers to buy it. It's remarkable when a first novel does well, but what was more unusual about "The Bridges of Madison County" was how passionately people responded to it. Everywhere, the story was the same. People would buy the book and be back the next day saying they'd stayed up all night reading and sobbing and becoming enraptured by a story so wonderful they wanted to buy more copies to give to their friends.

As spring gave way to summer, "The Bridges of Madison County" was turning into one of the most successful word-of-mouth books ever published. A few major newspaper reviews were harsh: The Washington Post lamented the book's "triteness," and the Los Angeles Times likened Waller's story to "Coke that's been opened a while ago: sweet but flat." But a more typical reaction was that of the ecstatic reviewer for the Orlando Sentinel, who called the book "as perfect as a tear."

The public, meanwhile, was smitten.

"I can't remember anything quite like it," says Margaret Maupin, a buyer for the Tattered Cover in Denver. "It's unusual for people to feel so strongly about a book. And it's a book everyone thinks they discovered."

Says Andy Ross, owner of Cody's in Berkeley, Calif., "It's kind of a four-handkerchief book. I don't know why people want to stay awake at night crying over a book, but they do."

In August "The Bridges of Madison County" made the New York Times bestseller list, where it has since remained. For the past two Sundays it's been No. 1 on the list, having sold some 420,000 copies after 19 printings.

Warren Cassell, owner of Just Books in Greenwich, Conn., says that for a time he wouldn't let customers out of the store without buying "The Bridges of Madison County." He's sold 1,000 copies and only a couple of people haven't cared for it. "It's every middle-aged person's fantasy," says Cassell.

Hero to the Middle-Aged

If Spielberg were casting the movie today, he'd find the prototype for Robert Kincaid in the soft-spoken man who answers the door at a modest A-frame in a secluded neighborhood. Robert James Waller is 53. He stands 6 feet 1 and is arrestingly thin but fit-looking. His silver hair is swept straight back from his forehead and curls over his shirt collar.

He is a vegetarian who smokes cigarettes and also jogs. He drinks instant coffee. He is partial to jeans, denim jackets and cowboy boots. "I come back into fashion about every five years," he says.

Waller has a sturdy ego. He says he based Robert Kincaid on himself, and Francesca, to a lesser extent, on his wife, Georgia Ann, a striking, dark-haired woman to whom he has been married for 31 years. (They have a grown daughter, Rachel, who lives in New York.) Waller has written a song based on the novel, and recently gave a one-man show here as a fund-raiser for a local hospital.

Waller is not a calculating man. He says he gave no thought to the book's commercial prospects as he was writing it -- even though it touches readers in much the same as did "Love Story," the syrupy bestseller of another age. No, Waller is different. If his book strikes you as hopelessly romantic and filled with meditative moments, then so would the man himself. "I'm not a very shrewd person," he says. "I wouldn't do well anyplace I couldn't trust people. I drive 55 miles per hour."

Waller's once-quiet life isn't that way anymore. He's unlocked a torrent of passion from the generation that came of age between the Great Depression and the sexual revolution -- and in the process he's become a hero to the middle-aged.

Admirers of the book call and write constantly. Georgia Ann admits they're considering getting an unlisted number. Recently a woman phoned to say she'd stopped by the house and taken a leaf from the yard to press into her copy of the novel. There's a consistent strain in what people tell Waller. "Some people call in tears," he says. "They say, 'You've given me hope.' A surprising number tell me they've had affairs just like I've described."

The story is told mainly from Francesca's point of view. In various places in the story Robert is called a gazelle, a leopard and "a star creature who had drafted in on the tail of a comet." He makes love like a wild animal, except he takes his time. Robert believes he's the end of an evolutionary chain that began in the Stone Age and is now winding down in Francesca's upstairs bedroom. As they make love, Robert says to Francesca, "I am the highway and a peregrine and all the sails that ever went to sea."

But for all its gibberish about ancient evenings and faraway places, the book is vividly romantic. It's racy in a deft manner -- explicit without being graphic. If he is not the best of writers, Waller is nonetheless an amazing storyteller, skillful in the ways that tend to matter most to readers. The book moves ahead relentlessly, but the speed is deliberate and the movements are graceful. It's like great foreplay: slow, intuitive, indulgent.

Waller says he worries about the lovers he created, Robert and Francesca, out there all alone. "They're quite real to me," he says.

And to others. A reviewer in Seattle was so convinced the book was true that she called the library to see if they had a copy of the National Geographic with Robert Kincaid's photographs from Madison County. A writer for the Daily Mail in London was set to come to Iowa to interview Waller until he learned the book was fiction. Distraught, he canceled his trip. "I certainly never meant for people to believe the book is literally true," says Waller. "I feel a little funny about it -- I want everyone to understand that this is a work of fiction."

Small-Town Childhood

Nothing tells you more about a book than the place it comes from. When winter sheathes the rolling emptiness of northern Iowa in snow and ice, the eye loses all depth of field. After the corn is down there are no lines of perspective; only an unceasing wind and the tractless monotony remain, and in it you feel alone and exposed. This is the middle of the middle of nowhere. The cold washes the color from even the sun, and the desolate sky matches the earth so nearly that you sometimes lose sight of the horizon.

Robert Waller was born Aug. 1, 1939, in Charles City, a short way from his parents' home in the tiny town of Rockford, a remote corner of the Iowa prairie harboring some 900 people. He grew up working for his father, a chicken and egg wholesaler. One of his earliest memories is of riding in the car trailing a roll of toilet paper out the window on V-J Day.

The town featured little in the way of distractions. There was a grain elevator, of course, and a brick-and-tile works, and a pool hall where Waller as a teenager once defeated the local three-cushion billiards champion. He spent much of his youth longing to travel. He was enthralled by the sight of the Rock Island Rocket passenger train that came through town at 9:10 every night, lights glowing tantalizingly from every window. Sometimes he'd get his father to drive him down to the trestle to watch the train rumble by. "I remember we'd park and my dad would lean out the window and listen," says Waller. "After a while he'd say, 'Here she comes, Bobby.' "

Waller spent most of his free time fishing and playing in two small rivers -- the Shell Rock and the Winnebago -- which arrived at their confluence just outside the Waller home. "It was a real Huck Finn existence," he says. And perhaps a lonely one for an only child. Waller remembers playing with an imaginary friend he called "Bigger."

He was a sensitive, intelligent boy at the center of a universe he largely devised for himself. He sometimes feigned illness to stay home from school and read in bed. He believed then, and still does now, that there are unseen wizards in the world, and that even inanimate objects are imbued with the spirit of life. "I think I've known for a long time that in the same way a big fish eats a smaller fish, someday the universe will eat me," he says.

At 13, Waller put up a basketball hoop in the yard. Day after day, he'd move across the packed dirt beneath the rim, dribble out, pull up and loft one jumper after another over the telephone wire that stretched across his makeshift court. His dedication was severe -- he would take the same shot over and over and over. Waller got good enough so that his father moved the phone line.

He made varsity as a 5-foot-2 high school freshman -- and then grew an astonishing eight inches in one year. Waller played guard, and despite being sometimes triple-teamed, easily scored 30 or 40 points a game. "I wasn't a very good team player," he says with a smile. By the time he left Rockford High in 1957 -- on an athletic scholarship to the University of Iowa -- he had set school scoring records that still stand. Basketball fans in Iowa, where the sport is revered as it is throughout the Midwest, remember Bobby Waller as one of the greatest pure shooters the state ever produced.

Waller transferred to Iowa State Teachers College here after a year, where he continued to play basketball and discovered a talent for mathematics that would lead to a PhD in economics from the University of Indiana. On weekends, often after a game, Waller would drive out to see Georgia Ann at her parents' home in Marcus in the western part of Iowa. It was a four-hour drive through the black Iowa night. Georgia Ann would make pizza while she waited, sometimes until 2 in the morning, for him to come.

"The first time I saw him, he was wearing black-and-white saddle shoes," says Georgia Ann. "And he had on a string tie, corduroy pants and a brown sweater with flecks of color in it. Real classy."

All along, Waller played music in bars wherever he lived. Once he and his partner were featured in a segment of Charles Kuralt's "On the Road" series. Another time they traveled with the Bobby Kennedy presidential campaign, troubadours in residence, as it were. Eventually he came back to Cedar Falls and became dean of the school of business at what had by then become the University of Northern Iowa.

One day in December 1985, overworked and worried about some investments in which he was sure he was being swindled, Waller suffered a "fatigue-stress" attack and had to quit his job. "It gives you all the symptoms of a heart attack except without the pain," he says.

For the next six years or so, Waller says he just sort of drifted, writing essays for the Des Moines Register, playing music, taking photographs and teaching a few courses in decision-making at UNI. Then came "The Bridges of Madison County."

The Literary Life

The Wallers built their home 15 years ago. The exterior is tongue-and-groove cedar planking. Inside, it's basic post-and-beam construction -- a functional design prized by Midwesterners who like it as well in their homes as they do in their pole barns.

The decor is quintessential college academic, circa the 1970s. Georgia Ann works downstairs at pottery and jewelry-making, sitting near the wood-burning stove in the middle of a south-facing atrium streaming with sunlight. At 50, her carriage remains that of the dancer she once trained to be; she looks as if at any moment she could rise from her workbench and glide across the room on point.

Waller writes in the loft that also contains a stereo and a neatly made-up double mattress on the floor. There's an enormous volume of books, magazines and papers piled on the well-worn furniture everywhere, an eclectic assortment in keeping with Waller's far-flung interests: "A History of Mathematics" lies on the floor near his desk next to "Infinity and the Mind." By the bed there's a copy of J.B. Priestley's "Man and Time," alongside an issue of "Guns and Ammo" from 1988. Then there are Waller's talismans: the big, heavy-action Calcutta bamboo rod his father used for catfish; a trio of bone-handled Mexican folding knives nailed to the wall near the word processor; a sun-bleached dolphin vertebra; a 10-inch gnomelike figure of a wizard in a tall hat. If you want to sit down, you have to move something.

Waller is a publisher's dream. With one book at the top of the bestseller list, he already has two more completed. "Slow Waltz in Cedar Bend," another romance, will be published in the fall. "I think Warner wanted 'Robert and Francesca II,' " he says. After that Waller hopes to bring out "Puerto Vallarta Squeeze," a thriller that's not only different in content but very different stylistically -- filled with stream-of-consciousness narration and hard-boiled dialogue. Waller says he rarely bogs down when writing.

The success of "The Bridges of Madison County" has given the Wallers a financial freedom they scarcely envisioned just a year ago, when they tapped their retirement account for $100,000 so Robert could continue writing. Their financial adviser recently asked them if they didn't want to buy something -- an expensive car, perhaps. But the driveway still holds only a Toyota 4Runner and a Dodge Caravan.

"I suppose we could travel," says Waller, considering some of their favorite places. "We could go to Paris. Or somewhere warm -- Georgia hates winter. We could go to India for six months."

They could, but will they? How do you know where to go with fame, how to spend success? How do you come from the middle of the middle of nowhere and in only 53 years understand what the world holds in store for you? Waller says that, growing up, he never knew all the things you could be, could only imagine the places you might visit. Now everything is possible, a pleasant dream made real.

Here in Cedar Falls, Waller is in some respects already a long way from home. He says his late father never even understood basketball, let alone anything of life beyond Rockford. "But he was very supportive," says Waller. "He tried to be part of it. I can still hear him. The stands would be full, thousands of people screaming, and as I'd bring the ball up court I could hear him call out to me, 'Go get 'em, Bobby.' I wish he were still around to see what's happening now."

One thing Waller believes in is letting his emotions live right near the surface, and sometimes they come out without the careful editing most of us apply to our sentiments. He is easily moved to tears when he speaks about his past, about growing up in Iowa and not knowing anything about the world except that he hoped one day to make his father proud of what he had become. He is devoted to Georgia Ann, to the life they've made together since they were teenagers.

Waller wrote it in his book, in a caveat to his story and maybe to his life in general. "Where great passion leaves off and mawkishness begins, I'm not sure." He bristles at the charge of excessive sentimentality that's been the principal criticism of "The Bridges of Madison County."

"Sure there's a line you can cross," he says. "I plead guilty to falling on the wrong side of it at times. There are some things in the book that make me cringe a bit -- I mean, some of it is way out there. I do get sentimental. But why is that an indictment? I am a sentimentalist, and I take a beating for it -- especially from academics. Of course, I have no faith in academics, having been one myself for 25 years."

"He intimidates a lot of people," says Susan Rueschhoff, a management professor and former colleague at UNI. "Some of it's jealousy, some people find him egotistical. I just think it's that when you're an above-average person, you can be seen as difficult. And he does seem to need a certain amount of isolation."

Well, he's not getting it now. Bobby Waller never was much of a team player, but he's making the best of the current situation, enjoying it actually. Life is good when you're above average in the Midwest. Maybe when the fuss dies down, Waller will find himself alone again and back in the place he started, no matter where he happens to be. He conveys a sense of being a man still on intimate terms with the boy he was. It's cold and empty out here right now, and Waller is working on the next installment of his own romantic education, one arriving in bookstores everywhere soon. It's coming easily, and with the same fluid assurance with which a boy once came bounding into the yard after a day on the river, picked up a basketball, dribbled right, then left, and rose up, eyes on the prize, and launched one high into the clear air over Iowa.