This is a novel to curl up with on a cold winter afternoon or a rainy spring afternoon or anytime at all. Easily consumed in one sitting, it is most definitely what is commonly called "a good read," having mystery and period charm and intriguing characters, and yet one hesitates to use that designation since it has come to imply a lack of seriousness, of literacy merit. "The Old Jest" has that too.

In a village outside Dublin, Nancy Gulliver is just turning 18 in August 1920, and, like the other literacy character who shares her name, she is embarking on a journey. Eagerly Nancy writes in the diary she has bought herself as a birthday present: "Today I want to start to become a person. My new year, my life, is ahead of me, empty like the pages of this book that I bought myself . . . maybe in 40 years' time I will like to know that the sun was shining on the day I first began to look at the world." Although she acknowledges that "there always seems to have been a war" and her Uncle Gabriel has been killed at Ypres, Nancy in the beginning is largely untouched by the current political upheaval -- "the Troubles" of Ireland's struggle for independence. By the novel's end, however, she will have learned the meaning of Turgenev's homily: "Death is an old jest, but it comes to everyone."

As a heroine, Nancy Gulliver makes one think of those strong-willed, independent young women who appear in the novels of Jane Austen or George Eliot. She is also, like a girl in a 19th-century novel, an orphan; her mother died giving birth to her "she gave me life . . . and I killed her. There's gratitude for you." -- and her father mysteriously disappeared, leaving the infant to be raised by an aunt. But despite the loss of her parents -- she searches the face of every middle-aged man she sees, wondering if one could be her father -- Nancy's childhood has been a happy enough one: "Aunt Mary is both mother and father to me, a really very satisfactory state of affairs." Now, reaching 18, Nancy is aware, however, that there is a world outside her village and she is eager to experience it -- to lose her virginity, which she considers a "great liability," and to become a writer -- and her desire for adventure and her curiosity annoy Harry, the sober, rather pompous, young man with whom she is in love.

Trying to understand herself, trying to sort out her feelings about Harry, who is in love with the more conventional Maeve, Nancy often retreats to a shack on the beach. It is there that she gets the adventure she has been looking for, in the person of a mysterious and kindly man who has also retreated there. It is through her involvement with this stranger, whose existence is known only to her, that Nancy comes to understand the need for change, for commitment to ideals, what is worth living for and what is worth dying for.

The bare bones of this plot sound ordinary and melodramatic. Yet such is the skill of Jennifer Johnston, an Irish novelist not well-known in this country, that she makes what might have been a merely sentimental romance into a convincing study of what it means to truly grow up, to accept the reality and absurdity of "the old jest" itself. This is a beautifully written, seamless novel by a writer from whom we should be hearing more, a writer whose spare and elegant prose puts her safely in the company of those of her countrymen who have made the art of storytelling an Irish national treasure.