Romancing the Giant : THE GIANT’S HOUSE: A Romance.<i> By Elizabeth McCracken (The Dial Press: $19.95, 259 pp.)</i>

If asked what Elizabeth McCracken’s first novel, “The Giant’s House,” was about, one would be tempted to describe the outrageous premise: A librarian falls in love with her library’s worthiest patron, who happens to be an 11-year-old boy, who happens also to be destined to become the world’s tallest man. An unlikely romance follows.

But what the book is really about is the narrator’s quest toward her own humanity. Librarian Peggy Cort, a wry intellectual, spinster material, declares in the opening passages of her memoir, “I do not love mankind.” She runs her Cape Cod library with sardonic dispatch, feeling vaguely unappreciated, certainly misunderstood, quick to judge others and herself, sensitive and lonely.

The story, told retrospectively, opens in 1950 and chronicles Peggy’s intimate friendship with James Sweatt, the giant. Eventually, the reader comes to understand that, although James is trapped in his personal bodily structure, Peggy is as elegantly trapped in her public one. Each acts as rescuer to the other, the profoundest “romance” imaginable.

While McCracken has successfully created both her narrator and her giant, the true pleasure in this lovely novel resides in the intelligence of the insights offered by way of Peggy. Her discriminating study of the human race, her shrewd observations about behavior and the resulting distilled aphoristic pronouncements she makes are the book’s true gifts to its reader.

“Despite popular theories,” Peggy tells us, “I believe people fall in love based not on good looks or fate but on knowledge. Either they are amazed by something a beloved knows that they themselves do not know, or they discover common rare knowledge, or they can supply knowledge to someone who’s lacking. . . . Nowadays, trendy librarians, wanting to be important, say, ‘knowledge is power.’ I know better. ‘Knowledge is love.’ ”

Who better, then, to navigate us through her subject’s brief stay on Earth? It is announced early on that James has died; the memoir is Peggy’s elegy, the story beyond the facade of sideshow freak. In fact, James is never allowed to reside for long in any scene in which his character might be abused, his feelings hurt. The reader does not have to expend energy fretting about whether his humanity will be recognized and cherished. That’s what Peggy Cort is for, loving him.

And loving him is what saves her. True, the story itself is a little short on story. But the premise is so engaging and the narrator so likable one can forgive a kind of slackness in the book’s body. It is, after all, sketching a romance, an unusual one that has required a great deal of care in explaining and illustrating, in making authentic. (One envisions the author having researched--in the library as well as in the heart--the idiosyncratic dilemmas of giantism, the ill-fitting shoes, the troublesome width of the typical stair step.)

The premise is a kind of double-edged sword, creating a kind of momentum, as well as an obstacle to be underplayed. A great deal of the characters’ 10-year relationship is relatively untroubled, by either external or internal conflict. Expected antagonisms--taunting classmates, thoughtless relatives, cruel mercenary businessmen--are practically nonexistent, as McCracken, wisely, is not interested in the freakish aspect of her material. Rather, she seems compelled by the opposite: the way in which an ordinary life can be made of the extraordinary, the way in which every human defies stereotype.

Peggy’s role as James’ caretaker is tinted by the possibility of other roles: mother, lover, teacher, disciple, friend. Her entanglement partakes of a variety of loves, all of which come to define “romance.” This is not a story about a woman seducing a boy who happens not only to be younger than she but the tallest person in the world. Instead, it is a tribute to the quiet passion of people trapped in isolation. James’ awkward body is no more an impediment than Peggy’s bibliophilism to the common business of a love affair. Neither is particularly prepared to be an average amorous sort--which is what endears them to the reader, who longs for their happiness, who also wishes to be unique and tragic.

Peggy’s triumph is in making the arc of her life resemble the unremarkable, familiar pattern. She has had her grand love, culminating in its own curious and coincidental way, and her progeny. She opens the book by protesting the proliferation of so-called interesting life stories, then proceeds to tell one that is worth hearing.