The first thing you notice about Richard Russo is his smile. It’s spontaneous, frequent, and hopelessly contagious.

Not that this is a surprise. Anyone who’s read one of Russo’s books knows he’s a funny guy. Plus, the author-screenwriter has plenty to smile about. His most recent novel, “Empire Falls,” made The New York Times best-seller list. People are still talking about “Nobody’s Fool,” which was turned into a movie starring Paul Newman. And the success of that book and film gave him enough of a financial cushion to pursue writing full-time and still be able to send his two daughters to college.

“That was kind of a watershed event,” Russo said during an interview Thursday evening at the Somesville Library in Mount Desert.

He was in town to read and sign copies of “Empire Falls” at Port in a Storm Book Store. Leaning back in his chair, dressed in a pair of khakis and a black polo shirt, he looked pretty relaxed for a man who wrapped up a 20-city book tour last month. Even though he’s a veteran traveler now, six weeks on the road and in the air is still draining. But he couldn’t turn down a visit to Somesville, especially since it didn’t involve flying or scarfing down a meal at the TGIFriday’s on Concourse C between gates 30 and 36.

“I’m like an old war horse businessman,” Russo said, breaking into that smile again. “I find myself with a lot of scary knowledge. I know a lot of airports by heart. I don’t have to ask for directions anymore.”

He wouldn’t trade it for anything, though. The 52-year-old Gloversville, N.Y., native came to Maine about 10 years ago to work as an English professor at Colby College in Waterville. Though he considered the job at Colby the best in more than 15 years as a professor, the money from “Nobody’s Fool” freed him to pursue his first love – writing.

Four years ago, he finished teaching. Shortly after, he and his wife, Barbara, and his then-teen daughters, Emily and Kate, moved to Camden.

“I love it,” he said. “There’s something about the combination of mountains and that incredible little harbor that you just don’t find too many places. … For a writer silence is pretty important and there’s also that – especially in the off-season.”

He now spends his days writing books there or working on screenplays with “Nobody’s Fool” collaborator Robert Benton in New York or Los Angeles.

“I’m blessed right now in a way that very few writers are.” Russo said. “I never dreamed – I wouldn’t have been arrogant enough to dream of doing this full time. I thought I’d always be a college professor. I would’ve done anything to be able to continue to write my novels at my pace.”

That pace is about one novel every four years. He thought it would pick up once he stopped teaching, but it didn’t. He’s kept himself busy working on screenplays for films such as “The Ice Harvest,” adapted from a novel by Scott Phillips, “Twilight,” and several Hallmark Hall of Fame productions, including “The Girl in Hyacinth Blue.” Those only take about six months to finish, though, because dialogue is Russo’s strong suit.

“It plays into what I do most effortlessly,” he told the crowd at Port in a Storm after his reading. “Writing a screenplay requires a hammer, a screwdriver and a few nails. Writing a novel requires the whole toolbox.”

He used every tool in his latest effort, a sweeping tale that weaves together the history of a Maine mill town called Empire Falls, its ruling family, and the decline of its textile industry with the story of Miles Roby, a man trapped there by circumstance. It all comes together seamlessly and ends with a bang – and a howl. But Russo rarely starts a book knowing how it will end. As he told the group at Port in a Storm, he writes novels for the same reason people read them – to find out what’s going to happen.

“I never have an idea for a book – I usually have a character that interests me,” he said. “I saw this poor guy as absolutely trapped. There’s just no way I could think of to get out of this pickle.”

Like Donald “Sully” Sullivan, the main character in “Nobody’s Fool,” Miles has few options. Though he started out with a bright future, finishing three years of college, he returned to Empire Falls shortly before his mother, Grace, died and has run the town’s diner ever since. He wants to go away, but he can’t. If he didn’t love his teen-age daughter, Tick, he could leave her with his ex-wife. If he had more money, he and Tick could move to Martha’s Vineyard. If he stays, though, he’ll be forever at the mercy of Francine Whiting, the mill owner’s widow, who controls everything in Empire Falls, including Miles.

“It’s not a nice thing to do to a person, but to find someone who’s good and trapped, that’s when I know I have a book,” Russo said at the reading.

Though the blue-collar characters in “Empire Falls” seem far removed from Russo’s own life as a former professor and renowned novelist, they aren’t. He grew up in a town like Empire Falls. His grandfather worked as a glove cutter. His father did construction work and bartending. His mother was a computer operator “back when there were a dozen of them in the country.” She wanted to go to college, but then she met his father. She made sure he pursued an education, though.

“She instilled … a sense of necessity in me much the same way that Grace Roby does for Miles in ‘Empire Falls,'” Russo said. “I have kind of educated my way out of the type of work that my father and grandfather did.”

Like Miles, Russo had a Catholic upbringing, though he hasn’t gone to church in a long time, “except in my imagination,” he said. That imagination formed Miles’ close ties to his Catholic parish. He’s friends with the young priest, he has volunteered to paint the church, steeple and all, and he has an almost saintly tolerance for the more annoying residents of Empire Falls.

“Once you’re raised Catholic it’s something you never quite expel,” he said. “It’s still the way I see things.”

While Miles is not Russo, there are bits of the author in Miles. Similarly, Russo used an image of his daughter walking home from school, lugging a backpack full of books, to introduce Miles’ daughter, Tick.

“Kate would come around the corner under that huge backpack, looking bent over and grim under all that weight,” he said. “I used that as a guiding metaphor – kids, carrying weight that they shouldn’t have to bear.”

Miles may be in a pickle, but the teen-agers in the book have their own problems – one has a history of abuse; another is trying to figure out her controlling boyfriend’s mood swings; a third is following in his father’s moronic footsteps.

For many of his characters, Russo uses a real person as a starting point and then lets the story take over. The same could be said for Empire Falls itself. In a sense, the town becomes a character in its own right – more so than in Russo’s previous novels. He attributes this to the time he took writing the town’s history.

“It’s really a book about the past and how the past intrudes upon our present lives and shapes our future,” he said. “In “Empire Falls” you get the history. I think that’s where you get the sense of the town. You get almost the sense of a character changing.”

The history of Empire Falls has shaped its residents’ futures in the manner of many Maine mill towns. Before anyone knew better or cared, the Knox River flowed through the town in vibrant shades of green or red, leaving a rainbow of stains on its banks. When it became cheaper to manufacture textiles or shirts elsewhere, the mill and factory closed, leaving the majority of the townspeople without work. Surrounding businesses failed. Storefronts emptied.

When readers ask Russo if Empire Falls is based on Waterville, where he once lived, he answers plainly, yes and no. It more closely resembles Skowhegan or Madison in its economy and geography, but it could be any mill town – Waterville included. At the reading, Russo told of a trip he and his wife took to several of Maine’s mill towns. They took pictures for the book’s Web site. When they got the film back, they couldn’t tell the towns, rivers, falls and buildings apart.

“Really, any town between Waterville and Rumford would stand in pretty well for my Empire Falls,” he said.

As the town’s reversal of fortune would have you guess, the double meaning of the title isn’t entirely coincidental. It came by accident, though. Russo originally called the town Empire Mills, but there were a lot of things going on at the falls in his fictitious town, and one day he mistyped the name as Empire Falls.

“I saw it and thought, ‘Wait a second, this is nice. I like that a lot,'” he said. “This book has a lot of empires falling. … Once I stumbled on that, I decided to let the words play.”

Of course, it made him smile.