Novelist Michael Thelwell says when he first visited Mississippi, he felt he'd seen it before.

"Reading Faulkner had done it for me," Thelwell explains. "He had painted all the scenery and the people. Chinua Achebe has done the same thing for eastern Nigeria. And I want my book to have the same kind of effect."

His book is "The Harder They Come," inspired by the Jamaican film of the same title that has become a cult movie on college campuses and in arty circles, and spawned the Jimmy Cliff hit reggae record in the early 1970s. Thelwell says he wrote it primarily for West Indian readers, and the Boston Globe calls it "a kind of novelized reggae, 'root music, dread music, their own.' This novel will also be discussed as a model of Third-World literature."

A first novel, it is the odyssey of Ivan Martin, who makes his way from underdeveloped rural Jamaica to the slums of Kingston, becoming a star reggae singer and gunslinging gangster in the process.

Though his novel is based on the movie's story line, Thelwell says it's not a novelization. "I fleshed out the story," he explains. "The movie didn't even have a screenplay. So I wrote about the daily lives of people -- their religion, folkways, food, phobias."

The movie opens with Ivan Martin as an adult, but the novel starts with his boyhood. The book bubbles over with aromatic -- and poetic -- patois and the harsh beauty of Jamaican country life.

The old man picked up an ear of corn and said, "Ah t'enk de Lawd for a good crop." There was a murmur of asent. "And Ah'm t'ankful for mi good frien' den who come yah tonight to help a ol' man." With a powerful twist of his wrists, he stripped the kernals from the cob. "What you see to eat, eat. What you see to drink, drink. Is nutten much, but whatsoever you see, you welcome to."

Like the real-life model, who called himself Rhygin (which means aggressive, spirited and passionate in the Jamaican argot), and who was killed in a shootout in 1948, Martin meets a violent end after a gunslinging spree.

Thelwell was particularly intent on making guns an important symbol in the novel. To be convicted of possession of a bullet, let alone a gun, in Jamaica usually results in life imprisonment. But guns are everywhere. Of 2,900 crimes committed there in the first six months of 1976, 1,662 involved firearms.

More recently, there has been violence because of food shortages, rising unemployment and a lack of foreign exchange. Even Prime Minister Michael Manley was shot at while visiting his home district in April.

"Guns are a real scourge in Jamaica," says Thelwell. "Social violence has become a real epidemic. The gun for Rhygin was a symbol he and his friends picked up from Grade-B Hollywood movies. I wanted to document the gun in simpler times."

The pistols lay on a soft cloth like an offering on an alter, gleaming in the half-light. The handles were of creamy, elaborately embossed mother-of-pearl, wickedly curved. The metal seemed to glow with blue life. Ivan swallowed and touched them tentatively. The sight of guns uncovered a need that he had not previously recognized . . .

"What a way dem jus' fit into me hand, dem," Ivan thought. Comfortably as though some distant gunsmith had measured them to his grip. They filled his hands, seemed to complete them as though his hands had been empty, unfilled before they come into them.

Thelwell says he keeps in touch with the tumultuous social and political climate in Jamaica by reading newspapers and magazines, and by corresponding with his brother, an engineer in Kingston. Growing up in Jamaica, says the author, gave him a feel for the people and the countryside.

"One of my students read the book and started crying," says Thelwell, a professor of literature at the University of Massachusetts, Amherst. "The man said, "That's my grandmother's kitchen. That's my grandmother!'

"Lots of black people have reacted that way. They see their own lives in the book.

"I spent time with the Rastas [Rastafarians, a back-to-Africa fundamentalist religious cult]," says the writer in an accent still thick with Jamaican honey. "I spent time with people in the rural areas. There's barely a line of dialogue I invented from my own genius."

"Mornin' Miss 'Mando. Glad to see you looking so well dis Lawd's day mornin'."

"Morning, Maas' Joe. And how is youself?"

"Healthy, thank de Lawd."

"An' you people dem?"

"Nothin' bothah them except hungry."

"Well," said Miss 'mando, eyeing the huge bunch of bananas that Maas' Joe was balancing on his head, "hungry better dan sickness."

"Is true, praise de Lawd."

"Well, 'member me to dem."

"Ah please to do dat. Walk good."

But Thelwell's own life was middle-class. His father owned saw mills and served in the Jamaican House of Representatives. His grandparents owned a 700-acre farm on which they grew spices, pimento and bananas.

Thelwell, 40, says he immediately liked the idea of doing the book when Grove Press approached him (Grove officials knew of him through his short stories and essays).

"I saw the movie as a basis for a socially conscious, politically conscious novel of Jamaica," he explains. "What you usually get is a Western travelogue, European or American. But the kind of novel Grove asked me to write is hard to sell to most publishers."

He pulls his lanky frame (over 6 foot 3) out of a slouch in his chair and waves his hands to make a point.

"Black writers should turn away from literary modernism," he says, slapping the arm of his chair. "Interiorization, the psychological studies -- all those should be abandoned.

"The black writer should look at the incredible gold mine he has. No one else has this relationship to people in the modern world. Look at the people we have to write about."

Thelwell reserves some of his angriest criticism for V.S. Naipaul, the critically acclaimed Trinidadian East Indian, who's written commercially successful novels and essays about the Third World.

"Naipaul has given Western intellectuals license to express their racism," he says bitterly. "People like Elizabeth Hardwick use his writings to say Africa is a crippled culture.

"Naipaul spends his time catering to the West rather than addressing the needs of his people."

Thelwell insists he isn't a political idealogue. He says he probably got his first taste of political action after coming to this country in 1959 as a 19-year-old student at Howard University.

There he edited the campus newspaper, won first prize in a short story contest and made friends with student activists Stokely Carmichael, Courtland Cox, Charlie Cobb and Cleveland Sellers, all of whom became involved with SNCC and the civil rights movement.

"We used to talk a lot of politics in the dorm," he recalls. "When they started talking about taking action, I didn't want to become involved. I was afraid of being deported. But when a bus came to take us down South, I had to either stay or go. So I got on the bus.

"When I went to Mississippi, I could see the struggle of poor black people very clearly. I saw that the life of the Jamaican farmworker was not far different from that of the Southern sharecropper -- in the way of courtliness, easy manners, language, proverbs."

Besides working in Mississippi, Thelwell also ran the Washington office of the Mississippi Freedom Democratic party between 1964 and 1965, and took part in the unsuccessful effort to unseat five members of the Mississippi congressional delegation.

"If those five members had been unseated," Thelwell says with heavy sorrow, "the history of the civil rights movement would've been different. Congress would've made a statement about itself. But it didn't happen."

In 1965, Thelwell went to graduate school at the University of Massachusetts and has remained in academia. He and his wife, Casey, who recently graduated from law school at Boston College, live in Amherst with their two children, Todd, 15, and Tracey, 12.

Thelwell, whose fiction-writing before the novel had been confined to periodic short stories, is planning another long work -- a novel about the civil rights movement. And he says it will not be literary subjectivism. It will flow, he says, out of experience.