It wasn't a good Christmas for Frederick Forsyth in 1969.

"I was just back from Biafra, out of work, out of funds, out of a flat. . ."

And a lot of illusions had gone in the ashcan, as he puts it now on a glittering day in Washington, flags snapping in the wind and millions of his novels scattered across the English-speaking world: "The Day of the Jackal," "The Odessa File," "The Dogs of War" (now a movie to open here Feb. 13). His latest, "The Devil's Alternative," has been near the top of the paperback best-seller list since it came out two weeks ago.

All this has happened since that dreadful Christmas back in England. He had left the BBC in a dispute over his reporting of the Biafran conflict, and was out of everything including "the assumption that the people who ran the world were men of good will. It's hard to believe that after you've seen a quarter of a million children die of starvation."

After a decade as a wire service and radio correspondent, all he had left was his "battered old portable typewriter, an Empire Aristocrat, the 1956 model. It had been around the world with me, in the bush with me, all over America with me as a Reuters correspondent, and the British Broadcasting Corporation . . . stringing for Time magazine after my fight with BBC over my Biafran coverage . . . but then it was clear the Ibos couldn't win -- and even though the British wer saying they weren't taking sides, they were sending clandestine arms to the federal troops . . . which only won by starving those people to death. . .

And so, at the age of 31, his youth seasoned to near-despair, he sat down at his Empire Aristocrat and wrote "The Day of the Jackal."

"It was only meant to be something to tide me over," he says now, screwing one of his 30-35 Rothmans a day into a cigarette holder. He lights it. He smiles.

Certainly it was a terrible idea for a novel, as four publishers pointed out to him. "They said: 'How can there be any suspense? You've got this assassin stalking DeGaulle in the eary '60s, and he's still alive.' They didn't get the point. The point was not whodunit, but how, and how close would he get?"

Having given away the ending before the book even began, Forsyth also created a protagonist who not only had no name, but no biography, no parentage, school or home town -- this in an age when the most popular thriller hero of all time, James Bond, was detailed down to the last wine label and custom-made cigarette.

"I didn't know I was being innovative at the time," he says.

He hardly had the time to think about it. He wrote the novel in 35 days. It's been making money for him for the last 10 years. (As have the movies made from it and "The Odessa File".)

Thrillers have been making money for a lot of writers in the last 10 years: Rober Ludlum, Ken Follett, Helen MacInnes, Trevanian, Alistair MacLean, John Le Carre, Len Deighton, Jack Higgins, Richard Condon, Hammond Innes, and on and on.

Usually, it's one man pitted against a world in which nothing is as it seems.

"Most people see power brokers and men of power on stage. I take them backstage. I show them the actors without their wigs, with their teeth out, I appeal to the curiosity people have as to how things get done in that world," says Forsyth, who for all of his millions has neglected to assume the aura of either the power brokers or any of his protagonists.

If it weren't for his gold Rolex, he could pass for a civil servant, a statistician, a florist. He is mild-mannered Mr. Average, 42 years old, complaining that our peculiar American practice of heating rooms above 62 degrees has brought on a "catarrh," by which he means a head cold. He has taken a Dristan. He hopes for the best. He is much like the rest of us.

There was the flap about the attempted coup in 1972, through -- the one that paralleled the events in "The Dogs of War." The Sunday Times of London reported that Forsyth had backed a takeover try in the West African state of Equatorial Guinea in order to create a new homeland for Biafran regugees; but the 13 mercenaries Forsyth supposedly recruited were arrested by Spanish police 3,000 miles short of their target, costing him $185,000, said the Sunday Times.

"I said I wouldn't comment then, and I can't comment now. I was given access in '72 to the clandestine world of arms dealers, and I had to give my word I wouldn't talk about it."

In other words, he was, in fact, hanging around the world of coups and mercenaries, at least for reasearch purposes. And that's all he'll say, except to add: "I suspect that story sold a lot of books for me."

If lend more authenticity to books that were already groaning with it: endless inventories of facts and proper names, techniques of obtaining end-use certificates for arms shipments, details on disassembling the Schmeisser submachine gun, the effects of a stuck pesticide valve on the Russian seed-corn supply, the ballistic characteristics of bullets containing droplets of mercury.

"I like the researching the best. I hate it in books when someone produces a gun, and you want to know where they got it and the author doesn't tell you. Of course here you can just walk into a store and buy one . . . I get letters from people who tell me they were reading one of my books on the beach in the Cayman Islands, and that I wrote about thier favorite resatauant, and got it just right, down to the name of the maitre d'. People like that."

But do they care enough to complain if he's wrong?

"I had one character greeting another in Jerusalem on a Saturday. He said 'Shalom shabbat.' Or 'Shabbat shalom,' I can't remember which way I had it, but it was the wrong way around, and I got letters about it.

"Before I started writing my books, I'd pull a paperback off a shelf in an airport store, and I'd say 'Jesus, I can do better than that, this is awful.'"

He includes no romance in his novels, outside of very brief and occasional sex scenes, because, he says, "I want to keep the action going. If I took 20 or 30 pages for a romantic interlude, the reader would end up forgetting what was happening."

His job, he says, is writing thrillers. He has no ambitions to transcend the form.

"Horses for course," he says. "It's an English expression, meaning that some horses are good for one thing, some are good for another. You run your stayers on heavy ground and you run flyers on light ground. I do what I do best, which is writing thrillers."

The odd thing about them is that so little of them is actually taken up by action, as opposed to meticulous detailing of facts, history, the metaphysics of intrigue, techniques for forging identity papers, buying 9mm ammunition, faking geological surveys, reading aerial reconnaissance photos and so on, ad infinitum.

But then, as he tried to tell the four publishers who turned down "The Day of the Jackal," that's the point.

The point is nicely proven now by a life which includes marlin fishing off Kenya, a manor house he spent four years restoring in Ireland, a house on the coast of Spain, and a new home back in England, where the conservative government has made the income-tax laws more appealing to millionaires such as Forsyth.

Is it possible he's won this success by appealing to the bureaucrat in us all? Huge portions of his novels are given over to people working their way through the protocols, mechanics and fine points of their lives. The fact that they're dealing with hand grenades rather than say, the regulations of the Department of Commerce doesn't mean that they're any less bureaucrats.

"That's probably right," he says. It's an idea which doesn't threaten him.

After all, look how many bureaucrats there are, spending their lives in the intricacies of procedure, and liking it.

Of course, we'd all like to think it could be a bit more exciting, that any of us could be sucked into behind-the-scenes battles of titans, that the blank form in the out basket is actually an order for 50 cases of Uzi submachine guns.

Wouldn't it be exciting to think so?

That's the point.