STARING AT THESUN<i> by Julian Barnes (Knopf: $15.95; 195 pp.) </i>

Imagine a fictional blend of “Tristram Shandy,” “Brave New World” and Flaubert’s tale, “A Simple Heart.” Or don’t, maybe. You could argue that there are suggestions of all three in Julian Barnes’ “Staring at the Sun.” But mixing such vastly different hues produces brown, and Barnes is never brown.

He is the English author of “Flaubert’s Parrot.” If its effervescence can hold still for a description, “Parrot” is playfulness seriously at work to transform the molecular movements of fiction into sub-atomic chain reactions.

In a formal sense, “Staring at the Sun” is more straightforward. In fact, it is more unconstrained. It is a religious book disguised as a game of wit and detour. As a final literary comparison, it is crookedly in the line of C. S. Lewis and his Anglican paradoxes. More skeptical, but with a skepticism that faintly smells of faith.

In Jean Serjeant, 99 years old in the year 2021, and remarkable for nothing in her life but a few disconcerting questions and one profoundly subverting action, Barnes has given us a sketch for a kind of saint of the near future.

Jean is the daughter of a modest English family. After World War II--she was 23 when it ended--she married a kind but stolid policeman; not for love, nor any leap of the imagination, but for lack of much else to do. Her imagination, as we shall see, was undergoing an entirely different schooling.

Life with Michael, the policeman, began with mild curiosity. Then, after an awful honeymoon, there came “the longer, slower dismay of living together,” Barnes writes. An initial companionability declined into rancor. There was no intimacy. “One and one always makes two,” Jean reflects. As for sex, “she thought of Michael as a tank that had to be drained once a month.”

A gray and quiet life, apparently; and a “Simple Heart” submissiveness. Except that, near 40, Jean unexpectedly gives birth to a son, Gregory. She leaves Michael and begins a wandering, odd-job life as a waitress in various parts of England.

There is no detail in any of this. The externals of Jean’s monochrome existence are set down by Barnes with a deliberate, charged sketchiness. The sketchiness is a judgment against the externals and in favor of something different. Jean’s departure is a transcendental statement. It declares that life is not simply what life offers.

And so, to the imagination. To the spectral or, if you like, the angelic life that disrupts and eventually informs Jean’s prosaic one. It is told in a series of witty portents and annunciations, conveyed by two unlikely archangels.

The first is Jean’s disreputable Uncle Leslie. He is the angel as con man. A con man, of course, is someone who seeks to climb over or duck under the rules of existence. In Jean’s humdrum childhood, Uncle Leslie is the harbinger of possibilities.

Her first recollection is a packet of hyacinth bulbs he gives her. They will come up later, he promises. They fail to. Finally, Jean unwraps them and discovers they are not bulbs but golf tees. “The Incident didn’t make her lose faith in Uncle Leslie,” Barnes writes. “Instead, she lost faith in golf tees.” The life of the spirit had begun.

Uncle Leslie takes her golfing, teaches her odd facts and curious sayings, and shows her a remedy for depression and failure: You lie down on your back and scream upwards.

Jean’s second corrupter into grace is an RAF pilot billeted with her family. He is a shifty man, but flying and dangerous extremity have given him an exhilarating voice. He tells Jean of pilots who commit suicide by climbing into the sun until they run out of oxygen, pass out and plunge into the sea.

This image and other from his life in the air kindle Jean’s inner life, her independent state of inquiry and her readiness--in her 90s--to accept the unseen. But as she retires and takes her questioning to such places as China and the Grand Canyon, the book’s center shifts to her son, Gregory. At 60, he has inherited his mother’s inquiring mind but not her serenity. Gregory boils his many urgencies down to three and asks his mother: “Is death absolute?” “Is religion nonsense?” “Is suicide permissible?” To which her answers are, in order: “Yes, dear.” “Yes, dear.” “No, dear.”

They may not sound like sanctity, but they are Barnes’ skeptical version. Jean herself wonders about them afterwards; she might well have answered differently. Because the important part is not the “yes” and the “no,” but the speed of reply, and the “dear.”

At the end, Gregory and his mother go up in a small plane to re-work the most magical of the images imparted to her over a half-century earlier by her RAF acquaintance.

Flying at dawn, he had watched the sun come up out of the English Channel. Then he descended thousands of feet, where it was still dark, and watched it come up again. A day of two sunrises. It is a trick, of course; but this is Barnes’ point.

Now, of course, the trick is reversed. She and Gregory go up at dusk and, climbing instead of descending, see the sun set twice. Death stutters. It is a hokey and surprisingly touching way for Barnes to finish this pulsating fable.