Had he been a brain truster, his critics would have advised him to return to New Haven, Cambridge or their equivalent, charging that he was on thin ice the moment he left the world of thought for the world of action. In reality Basil Pascali, Barry Unsworth's narrator, lived decades before the era of the brain trusters. The time of "The Idol Hunter" is 1908, the scene a Greek island near Asia Minor and on the edge of revolt against the Turks who rule the island. Pascali is of vague Mediterranean heritage. His mother was a dancer or acrobat who ended her days in prostitution. Possibly by his bootstraps, more likely by crime, Pascali raised himself from the gutters of Constantinople (if gutters there were), picked up a classical education and settled on his Greek island.

An islander by instinct and tightlipped about his own affairs, he pries endlessly and has for 20 years been a "paid informer" for the "Lord of the that speckle his reports to the sultan disappear when Pascali writes of his poverty. His clothes are an embarrassment, and when he goes hungry he isn't disciplining his fat, unwieldy body but accepting the consequences of an empty purse. Pascali is more sensuous than sensual, and he is quite at ease in his monkish way of life, softening its rigors now and then by stealing a book, a camera, field glasses.

The quiet rhythms of that life are suddenly broken. He fears that his occupation is known and that he will be murdered. When a moneyed Englishman -- such at least is his repute -- comes to the island, Pascali decides to use him as a means of escape. The bland Mr. Bowles lets it be known that he is an amateur archeologist and rattles on tireseomely about principle as if it were an English invention. Pascali begins to suspect that anyone who hints repeatedly that he is above board must be below board and deep, deep in guile.

Liking roguery, however, he develops a tenderness for Mr. Bowles and acts as a translator for the Englishman while he is negotiating with the authorities to lease land of supposed historical significance. One legend has it that the Virgin Mary traveled north after the crucifixion and died on an island in the Aegean. Mr. Bowles talks of writing a book on the subject of the Virgin's last home, and even though Pascali distrusts this bit of confidence and all else Mr. Bowles says about his plans, he relaxes in the Englishman's company and admits to being a spy on behalf of the sulton. The sultan, Mr. Bowles replies, "is finished," and he drops a word of pity on account of the vast paper work Pascali had devoted to a failing cause.

Sorting out his motives in the uneasy calm that closes his story, Pascali decides it was the pity that precipitated his treachery toward Mr. Bowles. What I assume ultimately savaged Pascali was Mr. Bowles' truth-telling. Pascali knew he was a comic figure to his neighbors and that it soothed their ignorance to see a scholar in near rags. Nevertheless, in a career he admitted to be ignoble, he discovered not only a palliative but a brilliant resource. He found that he had a literary gift, recorded the daily life of the island in masterly fashion, and assured that no harm would come to his neighbors by covering their activities under a gloss of fiction. Though he received his stipend regularly, no word of acknowledgement every followed his reports.

In "The Idol Hunter," as in his earlier novels, Unsworth is a Jamesian, finding drama, melodrama and sometimes comedy in racial and cultural contrasts. Mr. Bowles is the typical Englishman in his belief that he is eminently practical. His very person -- the athletic body, the searching eyes -- is a rebuke to Pascali, a reminder that he has spent his years in ill-rewarded thought, that he is a buffoon in appearance, that his efforts to please grate on the English spirit and give him the air of a toady.

First-person narrative lends itself to unlimited irony. For all his bitter complaints, it is clear that the island was a shelter ideally suited to an escapist like Pascali and that his taste for romanticizing was well served by the sea- and sky- and land-scenes that he described at happy, absurd length in his reports to the sultan. Escapism implies a rejection of the immediate experience and any lessons it might teach. iIt doesn't preclude a gift for delicate observation: Pascali's word-pictures of the natural world establish him as a latter-day Rousseau.

Apart from its exotic setting, "The Idol Hunter" has little in common with the traditional tale of espionage. Its suspense, though compelling here and there, pales beside the drama of pursuit and revenge that animated an earlier Unsworth effort, "The Greeks Have a Word for It." What "The Idol Hunter" offers instead is prose that charms from first to last, insights into an age of innocence that wasn't, and characterization that is convincing even when it depicts the contradictions and notes each turnabout of Unsworth's paid informer.