In the early 1930s, a young penny-a-word writer of detective yarns sold a batch of stories to the magazine Detective Dragnet, earned enough to get to Europe, and spent six months retracing the footsteps of a relatively unknown Dutch painter - Vincent van Gogh.
When he returned, he wrote a long, vivid biographical novel on the Dutchman - a novel spurned by 17 major publishers in New York and Boston, because Van Gogh was too obscure a figure.
But when Irving Stone's ''Lust for Life'' was finally published by Doubleday in 1934, it sold 800,000 copies and helped to make Van Gogh practically a household name. It even helped to popularize the French Post-Impressionists with which the painter associated.
This is part of the reason Mr. Stone was this week awarded the French government's highest literary honor, the insigne of Commandeur in the Ordeur des Arts et des Lettres.
It is also an acknowledgment of Mr. Stone's stature as one of the world's most popular tellers of the great stories of larger-than-life people - Van Gogh, Michelangelo, Charles Darwin, Sigmund Freud, and Jack London, among others.
The young Stone found that in writing ''Lust for Life'' he had lost his touch for the brisk, barreling plots that made him what he calls a ''very good writer of second-rate detective stories.'' But in the biographical novel he had found a form that is still absorbing his prodigious energies half a century later.
He likes the people he writes about. ''I won't write about anybody else,'' he says. ''I have to love my people.''
Straight nonfiction biography has never been enough for Stone, although he is generally credited with the accurate and thoroughgoing research of a first-rate historian. Stone's interest is in the emotional experience of dramatic, historical figures.
Like a method actor, he identifies closely with his subjects. He studies them for years, reading their correspondence, living in their locations, absorbing their environments, and attempting to experience their emotions.
''I go through the emotions that my people go through, both when they're battered and beaten and defeated and crushed and when they're successful and fulfilled and jubilant, because I don't think that you can convey emotion as a writer unless you feel it,'' he said in a recent interview. ''And that's how you get it down on the page.''
This led him to present Van Gogh's story as a novel, rather than as a detached, fact-bound biography. ''If I could identify totally with Vincent, I could tell the story from inside him. Not inside me. And that's what I tried to do, and that's why it came out as a novel.''
Stone lives high in Beverly Hills with his wife, Jean. She has been his editor on every book since she first read and tightened up the ''Lust for Life'' manuscript as his fiancee.
He has a well-ordered, book-lined studio, his secretary's office adjoining, at one end of the house. She has a cluttered, busy den full of bills, Rolodexes, and papers at the other end.
In the living room, crowded with statuary and wall art, partly obstructing the panoramic view of west Los Angeles, is a wall of books dubbed the ''Stone wall'' - some 800 volumes, each a different edition or translation of books by Stone. He looks at it, he says, when he needs to boost his writerly confidence.
He has produced 27 books. A total of nine and a half million copies have been sold. Some have been translated into 80 languages. ''The Agony and the Ecstasy, '' a 1961 novel on Michelangelo, has sold well over 2 million copies. It spent 13 months on the New York Times best-seller list and became a movie starring Charlton Heston.
Most recently, ''The Origin,'' a novel on Charles Darwin published in 1980, was also a major title on the best-seller lists. Stone is nearing the final drafts now of a biographical novel on the French Impressionist painter Camille Pissarro.
Stone's career as a historical storyteller has followed a simple map. About 30 years ago, he wrote on a sheet of yellow paper 10 people whose stories he wanted to write, adding a couple of lines on why each was a dramatic and universal human story. He has written nine of them (the 10th would involve an era he has already written on, so it lacks the appeal of a fresh challenge, he says); and he has written one that was not on his list.
His research has been called meticulous by academic historians. The notes for his current project on Impressionist Pissarro fill a chest-high filing cabinet. For ''The Agony and the Ecstasy,'' he went so far as to apprentice himself to a marble sculptor in Italy to understand Michelangelo better.
His writing day is a regular one. Stone starts writing every day at 8:30 a.m. , after a ''miserable breakfast'' (he's so keyed up for work that he doesn't eat much, he says). Lunch, too, is meager. Lately he takes a short midday nap and swim. Then he works until 5:30 or 6 p.m.
On an exceptional day, he will write six or eight pages. On a slow one, perhaps two. He writes in longhand. His secretary types the drafts on yellow paper. Mr. Stone goes through four rewrites of a section before Mrs. Stone sees a draft. Her extensive pencilings show careful, word-by-word editing on every page, with as much as a third of the writing lined out. After the Stones confer, Mr. Stone does one more draft before the manuscript goes to the publisher.
He regrets that more young writers are not setting out to write biographical or historical novels. He suspects that it is partly the great expense of doing years of research, especially overseas, and partly that the projects are simply too arduous.
''They don't want to do that much research,'' he says. ''They want to write about how much they hated their fathers or something like that.''
He reflects on seeing the 50th-anniversary edition of ''Lust for Life'' come out this year, with the book still in print in many languages, and him still actively writing.
To find other American writers that have had that experience, he muses, ''you almost have to go back to Mark Twain.
''When I think of that,'' he adds, ''I think maybe some of these other books are going to last.''
Some critics have charged over the years that Stone is a better biographer than novelist, or that in his sympathy with his subjects he idealizes them too much.
Regardless, the public has had an appetite for his large-canvas sagas of human drama.
''If they were phony, if they were thinly researched, if the conclusions and the emotional buildups and all were unbelievable or false and people didn't accept them, they would never sell and never be read.
''Readers can smell the phoniness through the print. That's my basic conviction. And if they accept the books, it's because they feel this is real and this is honest and this is true and I can depend on it, and I can enjoy it.''