In an outpouring of literary allusion toward the end of "Green Monday," the novel's hero spouts snippets of popular poetry as he looks back on an oily trail of fortune, jingoism and murder. But they come far too late and are much too cloying ("Into his head swam lines of Cummings: 'And how do you like your blue-eyed boy Mr. Death?'") to keep him from being an essentially dull fellow.

But we don't ask of this author, a 44-year old businessman who has looked up from his ledgers to peer at larger dimensions, that he draw Dostoevskian characters. Making profits and making art tend not to mix. What comes of institutional-experience-turned-fiction is more commerce, bigger trade, different exchange, like, say, Alan Trustman's daydreaming over the roof of a Boston bank that grew into "The Thomas Crown Affair."

The dimension Michael M. Thomas has given us in his engrossing first novel is, to put it simply, the conduct of business on the largest scale imaginable. The numbers are numbing. That Thomas manages them without spilling over into the absurd is one of this hefty volume's many pleasant surprises.

What happens, basically, is that a free-lance investment banker from Wall Street undertakes a clever crusade to save the country from fools (that Thomas presumes this can be done is one of the book's few lapses of credibility) and make himself rich at the same time by programming three oil-rich Arabs to invest $5 billion in our stock market, and then announce a reduction in the price of oil. The surprise cut sends the market soaring, of course; its 68-point gain gives rise to the title "Green Monday" (as opposed to Black Tuesday).

The power barons (some only thinly disguised from real persons living or dead) who get involved in Thomas' skillfully contrived plot are set against the backdrop of a festering hemisphere. Our hamstrung pig-farmer president named Baxter and his chief adviser are plotting a war in order to capture Mideast oil fields. Times are so bad in America that bluebloods in Boston are forced to sell their Copley paintings just to pay their heating bills. The constituency is angry and impatient. For their part, the Arabs recognize that their buying power diminishes as oil prices increase. The laws of supply and demand no longer apply, and they are spinning their wheels while Western economies threaten collapse. They realize that Marines could easily be pumping gas tomorrow in their back yard, and they sniff out a grand opportunity to manipulate the presidency at the next election, and thus own the whole country. It makes for chilling verisimilitude.

Thomas reflects on the cruel world of money and the monied world of crude -- sensibly, not at length. Though he obviously delights in deflating bankers, tycoons and B-school sycophants, he rightly chooses intrigue over philosophy. The book's least rewarding moments come in ironies that tend toward satire but end up ridiculous. The president is irrelevantly portrayed as so Southern that he takes lessons to learn to speak English, and so berserk with born-again fever that on national TV he introduces his "SAGG" campaign -- Save a Gallon for God (throughout, the author's enchantment with acronyms cannot be shared). The Arab oil minister is unctuous, and his sidekick a died-in-the-wool bugger. When the Dow Jones Index doubles in six months and America goes on a binge, General Motors plans a 12-cylinder engine "to power the biggest Cadillac ever." And our energy secretary is an out-of-it buffoon who can't recognize an oil rig when he's shown one.

But, unfortunately, the most serious relationship in the book is also the least interesting. The hero and his ex-Weatherwoman cohort have little to say to each other, even as a continual parade of potenates, tycoons, financiers, hired guns and assorted other expensive bodies passes in review. Instead, the lovers are forever groping toward quickie sex bouts that culminate in some unknown dark region outside the author's sensibilities. Just as well, though. When Thomas turns to vivid writing, the words come out like a Victorian potboiler, and his ear for dialect is even worse.

But when all is said and done, money talks best, spinning a gripping and revealing tale beyond the workaday world of sodomists, jargon-spouting stock-market analysts, Greek shippers and other stereotypical establishment types with whom Thomas has filled his landscape. An investment banker and financial consultant, the author clearly knows this arena best. Money -- this much of it -- breeds a kudzu vine of stupidity as well as cupidity; it absorbs and compels, advances and ruins. Thomas directs its cause and effect with a spy-story dynamic that is as compelling as any novel more truly in the genre.