MARTIN AMIS has written a big brave book. It is amply endowed with flaws, as most big brave books are, but they are entirely overshadowed by the breadth of its ambition and accomplishment. It takes great risks, it boils with energy, it gives offense, it even manages -- this in an age when nothing any longer seems unexpected or surprising -- to shock. And for all of that it is so unremittingly, savagely hilarious that reading it is quite literally an exhausting experience, from which one emerges simultaneously gasping for air and pleading for more.

Money is not a book for everyone, though it is rather difficult to say with any confidence who are the ones that will like it and who are those that will not. Most certainly it is, in the word of the English friend who alerted me to it, "scabrous": "dealing with," as Webster has it, "or characterized by suggestive, indecent or scandalous themes," not to mention "unpleasant, repulsive or reprehensible in some way." From first page to last it is one long drinking bout, interrupted only briefly by a period of relative sobriety; it contains incessant sexual activity, much of it onanistic; it has a generous supply of sordid language that would not pass muster in polite society; and it has an unkind word for just about every race, creed or nationality known to exist.

Scabrousness on such an overwhelming level ordinarily would offend me, as I have come to believe in recent years that it exists in most contemporary fiction principally to call attention to itself and to the person who is writing it. But it is impossible to imagine Money without it. That is because Amis has done something entirely remarkable: he has created a central character of consummate vulgarity and irresistible charm, and he has insinuated himself into this character so completely that the voice with which he speaks is that man's and that man's alone. In Money we listen not to Martin Amis speaking through John Self, but to John Self speaking through Martin Amis. We go a long way back -- perhaps all the way to the Compson children in The Sound and the Fury -- to find a novelist so utterly possessed by his narrator; the result, as they say in the macho world John Self inhabits, is awesome.

"Me I'm five foot ten and sixteen stone." That's John Self speaking. "I have this zooty look, the boxy jacket and the python strides, the bright socks and the black suede shoes, the indeterminate, driven-back hair, the beady scaly face, the face of a fat snake, capable of sudden obedience, sudden revolt." Put the image of John Candy in your mind and you've got the picture of John Self: obese, outrageous, wily, innocent, infuriating, loveable. In the fast-track world of the late 20th century, John Self is Everyman: perpetrator and victim, exploiter and exploited, cynic and naif. Like Everyman, John Self wants it now and wants it all; it's the getting of it all that proves a bit difficult.

HE'S A 35-year-old Englishman, "one of the top commercial directors in the country," now preparing to make his first feature film, tentatively called Good Money. It's a transatlantic affair, bankrolled by Fielding Gooney, "my moneyman, my contact and my pal," an American smoothie whose own moneymen "talk about money in that sharky American style, as if money were the only gauge of anything, the only measure." Back and forth across the Atlantic flies Self, in perpetual motion between London and New York, wallowing in money and booze and women and accomplishing almost no work at all. As he says: "With business I'm usually okay. It's pleasure that gets me into all this expensive trouble."

Trouble is scarcely the word for it. There are, to begin with, the things he does to his body: "My head is a city, and various pains have now taken up residence in various parts of my face. A gum-and-bone ache has launched a cooperative on my upper west side. Across the park, neuralgia has rented a duplex in my fashionable east seventies. Downtown, my chin throbs with lofts of jaw- loss. As for my brain, my hundreds, it's Harlem up there, exploding in the summer fires. It boils and swells. One day soon it is going to burst." There's the smut to which he is powerfully drawn: "Why do they happen to me, these numb, flushed, unanswerable, these pornographic things? Well, I guess if you're a pornographic person, then pornographic things happen to you." There are even matters as simple as putting on a rented tuxedo:

"A jungly night in New York, and the outer heat was proving far too much for the theater's thrashed cooling systems. I began to notice that an impressively candid odor was seeping from my hired jacket, not one smell but a deadly anthology of fatso emanations, the trail of the thousand soaks and sweats who had used it before me and would use it again when I was done. The people behind, were they getting wind of me? Martina herself now frowned and sniffed. Each time I squirmed in my seat the jacket selected another noxious parallel from its quiver. Either it was paranoia of the nostril or I was getting the lot here: ashtrays, soup-kitchen explosions, used stalls in porno emporiums, magazine wax, booze bubbles. No question, this bit of shmutter had done time on some very fat, hot and unhealthy guys. I scratched my nose. Pew. There came another wicked fart from my right armpit. Martina sniffed and writhed. Gently does it, I thought, and searched for a state of fixity and trance."

Such a state is not in the cards for John Self. He is "addicted to the twentieth century," and chaos and confusion are his lot: "It's the twentieth-century feeling. We're the jokes. You just got to live it. . . . You just got to live the joke." He reels about from indulgence to outrage to eruption, forever fancying himself to be in charge but always, in actuality, dancing to someone else's tune. Among those calling the tunes are Fielding Gooney and the moneymen, the bizarre melange of third-rate actors and actresses who populate the set of Good Money, and the women who slide in and out of his life.

Women are a problem for John Self. He imagines himself a wow with them, but they tie him in knots. His semi-live-in girlfriend in London, Selina Street, the embodiment of his pornographic fantasies ("whose appearance, after many hours at the mirror, is a fifty-fifty compromise between the primly juvenile and the grossly provocative"), leaves him in her absence with "a new pain, a new squeeze right in the ticker." She betrays him this way and that, in the end by an act of unfathomable cruelty, yet he keeps coming back for more, so imprisoned is he by his appetites and thirsts: "The thing about Selina is, she understands. She knows the twentieth century. She has hung out in cities . . . When we go to bed together, sometimes the conversation turns to . . . While making love, we often talk about money. I like it. I like that dirty talk."

Money's what he thinks he's got because it seems so easy to get. Here's a grand a day, Fielding Gooney tells him: you don't look right if you're not spending big money, making waves, showing your stuff. But it's all an illusion, and a delusion. It's all words, and all of them are lies. It's just like the business of seeming to be in control: what John Self thinks he sees is not what he gets. In a moment of guilt Self tells himself: "I must marry Selina. If I don't I'll just die. If I don't, no one else will, and I'll have ruined another life." But with love as with money, Self has it all backwards: it's not he who's ruining others' lives, but others who are ruining his.

For John Self, though, this is only the beginning. The greedy man as unwitting 20th-century victim may be the central business of Money, but an awful lot of other stuff is going on as well. There is a mysterious telephone caller who may be Self's conscience and may be his manipulator: Who knows? There's the surprising -- and to my taste neither obtrusive nor gratuitous -- introduction of a character named Martin Amis, a young British novelist who lives in Self's neighborhood and eventually gets involved with the movie. There's an extraordinarily vivid depiction of contemporary Manhattan: "Heat, money, sex and fever -- this is it, this is New York, this is first class, this is the sharp end." There's show biz: "Davis' agent was there, Herrick Shnexnayder, a desperate human being who wore a French smock, a prosciutto cravat and the most complicated double pate-job I have ever come across in ten years of show business. One yellowy hank was swiped forward from the nape of his neck, while the other originated from his luxuriant left sideburn. His head looked like a fudge sundae -- I swear to God, he could have put a spoon in his ear and a maraschino cherry on his crown and looked no worse." And through it all is the sense of dread: "I have a sharp sense of my life being in the balance. I may never look back, or I may never recover. I tell you, I am terrified. . . ."

IN FACT, there is so much in this novel that a review can only begin to suggest it. Its principal shortcoming, if anything, is that ultimately there is too much; the book is too long and, like John Self, is in constant danger of spinning out of control. But this may well be the madness in Amis' method. If there is excess here, then there is also excess in John Self and excess in the 20th century he so pornographically and flamboyantly mirrors. This is his novel, all right -- call it "John Self: His Own Book," if you will -- and in it he emerges as one of the indisputably memorable, not to mention haunting, characters of postwar fiction. He is an outrage in every word and action, yet it is impossible not to love him. His greed is deplorable, yet his innocence redeems him. He dreams, he yearns, he desires; so, alas, do we all. CAPTION: Picture, Martin Amis. (c) 1985 by Jerry Bauer