The Chess Match of History : THE EIGHT<i> by Katherine Neville (Ballantine Books: $18.95; 550 pp.)</i>

The only obligation to which in advance we may hold a novel . . . is that it be interesting, wrote Henry James in “The Art of Fiction.” Katherine Neville’s impressive first novel, “The Eight, “ is exceedingly interesting, to say the least.

It incorporates elements of adventure, mysticism, fantasy, romance and murder mystery; there are two main interwoven stories, one contemporary, one set two centuries ago; historical figures abound, such as Robespierre, Marat, Talleyrand, Wordsworth, Catherine the Great, Sir Issac Newton and Napoleon; the fictional characters are uncommonly diverse, including a computer expert, chess champions, nuns, an Algerian oil minister and a furrier.

All these disparate ingredients coalesce to form a fascinating piece of entertainment that manages to be both vibrant and cerebral. Like Rubik’s Cube, “The Eight” demands to be pondered. Few will find it resistible.

The novel opens on April 4, 1790, at isolated Montglane Abbey in France. Gravely, the abbess assembles the nuns to tell them an astonishing tale. For 1,000 years, a magnificent jeweled chess set known as the Montglane Service has been buried within the Abbey’s walls and floor. Bestowed upon Charlemagne by eight Moors from Barcelona, the Service is still coveted by many because, as Cardinal Richelieu wrote in 1642, its squares and pieces contain hidden clues to a potent secret formula capable of causing “the fall of civilizations and the death of kings.”

The abbess orders her nuns to unearth the Service immediately, and she commands them to conceal its pieces in far-flung locations so that ruthless French anarchists can never wield the formula. Two of the nuns entrusted with this hazardous covert mission are youthful friends--Mireille de Remy and her irrepressible cousin, Valentine.

In accordance with the abbess’ instructions, the girls seek shelter at the Paris home of Valentine’s guardian, painter Jacques-Louis David. The city seethes with feverish mobs eager to destroy the Catholic Church and monarchy, while vipers such as Marat and Robespierre stealthily hunt for the Montglane Service.

After Valentine is put to death for her knowledge of the prized chess set, Mireille vengefully decides to retrieve all its pieces. She leaves her lover, Talleyrand, and embarks on a risky, arduous journey that requires every ounce of her emotional and physical stamina.

Interspersed with Mireille’s saga is the story of her modern-day counterpart, Catherine (Cat) Velis. In 1972, Cat, a computer analyst for a New York accounting firm, icily refuses her boss’ request to perform an unethical deed. For punishment, he banishes her to Algiers to develop a computer system for OPEC (which, coincidentally, is one of author Neville’s own accomplishments).

Cat attends a New Year’s Eve gala prior to her departure. Two portentous incidents occur there: An antique dealer asks her to locate the Montglane Service in Algiers for one of his clients, and a fortuneteller makes a cryptic prediction. Warning Cat of imminent peril, she mutters something about chess squares and secret doors before saying, “On the fourth day of the fourth month (Cat’s birthday), then will come the Eight.”

Unfazed, Cat goes looking for the Service nevertheless, tumbling into one life-threatening predicament after another along the way. Just as Mireille did generations earlier, however, she gamely keeps searching for Charlemagne’s treasure, certain that the formula disclosed by those mute chess pieces will convey “the voices of the gods.”

Neville does many things deftly in “The Eight.” The book is strikingly offbeat, witty, engaging and briskly paced. It combines aspects of several different genres, yet the overall effect is intriguing rather than haphazard. Although some outlandish plot twists take place, Neville handles them so authoritatively that only the most rigid sticklers for veracity might flinch.

The historical passages also deserve praise. Neville excels at portraying the manic climate of revolutionary-era Paris, and the ferocity of those who led the uprising. She neatly integrates actual people with fictitious ones; her descriptions of notorious individuals are often memorable.

A few succinct lines suffice to depict the loathsomeness of Marat: “The man was hideous. His flesh was a mass of scars and suppurating sores. A filthy rag was tied about his forehead, dripping with a dirty-colored liquid that trickled down his neck and matted his greasy hair. . . . Mireille thought that the pustulating wounds that covered his skin must have oozed up from the evil that lay within him . . . .”

The novel brims with references to chess, mathematics and coded messages, all of which concern the Montglane Service’s elusive formula. These references do give “The Eight” a quirky kind of depth and individuality, but they can be baffling too. For example, Cat’s detailed explanation of a Pythagorean concept may totally confuse anyone unacquainted with such topics. In general, intellectually nimble readers who relish mental “gamesmanship” will probably savor “The Eight” most keenly.