The Beat of the Humdrum : HAPPY ENDING <i> By Francesca Duranti Translated from Italian by Annapaola Concogni</i> (<i> Random House: $17.95; 165 pp.) </i>

Our lives are not books, of course, but they too need their pages turned. Sometimes, like the characters in a novel, we are unable to reach out and do it ourselves. And then, however brilliant the page may be, it goes stale. Dostoevsky could write the Grand Inquisitor scene, but it is the ordinary, much less splendid reader who turns the page when it is over, and goes on to the next chapter.

Stage hands, in a sense, are as important as the actor playing Hamlet. The carousel’s prancing horses would lose all grace without the mechanism that ratchets them off along the circle that takes them away and brings them back.

The Italian commedia dell ‘ arte was built upon that circling, page-turning rhythm. Its power came not just from its stylized characters and what they performed, but from the larger pattern in which they were set. A final procession--often in a circle--would bring back Pantaloon, Columbine, Harlequin, Pierrot from their assorted mishaps, intrigues and heartbreaks to proclaim that their suitcases were packed, and it was time to move on to the next town.

In a sense, Francesca Duranti’s lovely novel, partly a comedy of manners and partly a harsher and more magical commedia , is about a page-turning. The fragile order of a wealthy old country family--a patchwork of arrangements, compromises and secrets concealing an array of angry passions--is threatened by the approaching demise of its matriarch and chief patcher. It is unlikely to survive, yet no one--not the old woman herself, nor her favored daughter-in-law who is supposed to carry on, nor another less-favored daughter-in-law, nor her son--seems capable of taking hold.

And then a stranger arrives, a seductive young man with a mysterious faculty for disruption. When he leaves, they all have more or less been wrenched from their moorings. Out of the drift, a new balance appears, very different yet remarkably like the old one. The mysterious stranger, it turns out, is ordinary and oblivious. He is the simple passage of time, which so often arranges what it disarranges. He is your humdrum page-turner. He is the beep-beep of the rickety bus waiting to take the traveling players to the next town.

“Happy Ending” plays its story of decline and renewal as a grave theme scored for light orchestra. The plot is as playful and contrived as a masked ball; the colorful masks heighten the complex intentions of the dancers by concealing them.

The narrator is Aldo, a wealthy art expert who rose from a humble beginning as a pottery restorer. His mother, who taught him the trade, had higher aspirations. “I will not rest in peace,” she told him, “until I see you all dressed in white behind the counter of a pharmacy.” Aldo’s aspirations were higher still. Nevertheless, he dutifully fills at least part of his mother’s by dressing in finest of white linen suits.

He also wears purple silk pajamas, lives in a simply but magnificiently furnished 13th-Century tower, and is served by a devoted elderly couple, the very image of two old family retainers.

“Image” is the point. Scavenging for food as a child, Aldo had peeked through the window of an aristocrat’s house and seen the family at dinner. It aroused an unquenchable hunger to be like them. From pottery-restoring, he became the most skillful of art forgers and this--forgery being the deepest form of study--let him go on to become a legitimate, honored and rewarded dealer and expert.

It is Duranti’s graceful irony, and it is more. Aldo’s desire for the world of fine old things has led him through fakery to truth; but is there a difference? His “old” retainers are a newly hired storekeeper couple. And all his passion for the previous 20 years has been directed to the Santinis, the leading family of the vicinity and owners of the three villas in the park adjoining his tower.

Aldo is a confidante of Violante, the witty and graceful old woman who, widowed, is head of the family. Since she was 15, he has been hopelessly in love with Lavinia, who married Violante’s elder son, was widowed shortly thereafter, lives in Milan but comes regularly to stay. He is a close acquaintance of the second son, Leopoldo, who runs the family business, and of his American wife, Cynthia; the couple lives in the second-largest of the three houses on the estate.

Aldo is regularly in and out, a trusted friend and counselor. And when he is not actually there, he is at a tower window, watching the Santinis through binoculars. He has been a spectator at the play, he tells us; his entry as an actor will be one of the changes set off by the brief visit of Marco, a friend of Lavinia’s son Nicola, who is studying in America.

The Santinis, with their lands, their feudal care of their workers and the unostentatious charm of their possessions and their comforts are, to Aldo’s eyes, like a beautiful 16th-Century credenza. To put it this way is to notice once more Duranti’s braiding of imposture and truth. It is true that Violante is a great lady; it is also true that she came from a poor family and married up.

Entirely genuine or not--anything seen through Aldo’s and Duranti’s eyes has this lovely ambiguity--the credenza is undeniably worm-holed. Violante, mistress of a thousand fine-tunings--ordering enough panettoni for Christmas, remembering the wedding present for a tenant’s daughter, getting the upholsterer in--wonders if any of the next generation can learn the minute tasks that maintain a world.

“They saw her do each of these things, and many others besides,” Violante worries, “without ever realizing that all of them taken together . . . meant ‘to reign.’ ”

Her plans for succession are on Lavinia, widow of her favorite son and mother of Nicola. But Lavinia, abused by her husband--he slept with his mistress on their honeymoon night--and later by a succession of lovers, is scatty and insecure. Living in Milan, she left Nicola to be raised by his grandmother. The old woman draws diagrams of her worries and shows them to Aldo: How can she get Lavinia and Nicola back together? How can she get Lavinia to be a real mother instead of someone “who judges herself by her effect on others.”?

Leopoldo and Cynthia seem equally undependable. As an American, Cynthia thinks of herself as an outsider; furthermore, she refuses to have sex. No succession there, it seems.

Then Marco hitchhikes through. He is spoiled and self-centered; he is beautiful and suspect as one of Aldo’s old paintings. Everything changes. Lavinia sleeps with him and suddenly his selfishness transforms her; she will move back to the estate, become a real mother, fall in love with Aldo, her suitor of 20 years, and finally bring him into the family.

Leopoldo and Cynthia, similarly besotted, find, by a similarly arbitrary and magical illusion, a passionate lust for each other. Violante’s cobweb plans for the future, resting on Lavinia, collapse, only to be replaced by something unexpected and more solid. And Marco turns from brief demigod to one more boring young man who departs the next day, to everyone’s satisfaction.

Duranti, author of “The House on Moon Lake,” is a writer of rare delicacy and power. “Happy Ending” is all gleaming surfaces, and you would think that under these surfaces only the most elegantly witty and ironic forms of life would swim. Suddenly, there is a fakey incantation--if Aldo, Violante and Lavinia are finely-drawn portraits, Cynthia and Marco are carnival masks--and dark and violent forms break water for a moment. For a moment, the weather changes, and then everything is as serene as before.

Life is the civilized and nuanced page, and time is its hobgoblin page-turner.