By A.S. Byatt

Random House. 555 pp. $22.95

Book critics are paid to offer informed, careful judgments, full of erudition or good sense or both, but sometimes all we really want to say about a novel is "Wow!"

A.S. Byatt's "Possession" is that kind of book. You turn its last page feeling stunned and elated, happy to have had the chance to read it. At once highly traditional and eminently postmodern, this is a novel for every taste: a heartbreaking Victorian love story, a take-no-prisoners comedy of contemporary academic life, and an unputdownable supernatural mystery that starts with an old book in a London library and ends on a storm-wracked night in a churchyard before an open grave. It is above all an uncanny work of literary impersonation, for Byatt re-creates the letters, journals, poems, fairy tales and critical writings of a dozen characters, and interlaces them all with common leitmotifs, recurrent imagery and other subtle connections. Imagine some impossible hybrid of Robertson Davies, Iris Murdoch, Anthony Burgess and John Fowles, all writing at their very best, and you'll have an inkling of the pleasures of "Possession."

"The book was thick and black and covered with dust." In this old volume (of Vico: a hint) Roland Mitchell, a young, somewhat dull textual scholar, stumbles upon the draft of a letter written to an unknown lady by the distinguished Victorian poet and model of marital propriety, Randolph Henry Ash. "Dear Madam, Since our extraordinary conversation I have thought of nothing else," it begins. The sentences betray such unexpected emotion that Roland surreptitiously pockets the manuscript, telling no one of his discovery.

Internal hints in the letter soon lead him to Henry Crabb Robinson's voluminous diary, from which he figures out that the lady in question must be the reclusive poet, Christabel LaMotte -- who, it had been thought, never knew Ash. LaMotte is currently a hot property in academic circles, generally regarded as a lesbian and protofeminist, author of exquisite lyrics, some curious fairy tales and an almost unreadable epic about the serpentine fairy Melusina. Pursuing his quest, Roland calls on the icy Maud Bailey, a leading expert on LaMotte (author of "Melusina, Builder of Cities: A Subversive Female Cosmogony"), and the two team up to piece together the clues of the mystery: What happened in the summer of 1859 between Randolph Henry Ash and Christabel LaMotte?

As these scholars sleuth their way through the library stacks and country houses of England, Byatt duly transcribes what they turn up: the documents in the case. In Lincolnshire the researchers uncover a cache of letters: "I read your Mind, my dear Mr. Ash. You will argue now for a monitored and carefully limited combustion -- a fire-grate with bars and formal boundaries and brassy finials ... But I say -- your glowing salamander is a Firedrake. And there will be -- Conflagration." LaMotte's poems take on deeper meaning: "This is our doom/ To Drag a Long Life out/ In a Dark Room." And entries in Ellen Ash's unpublished journal point to further riddles: "Another letter from the mysterious and urgent lady. A matter of life and death, she writes. She is well-educated ... I put the letter by, feeling too low in spirits to decide about it."

R.H. Ash is modeled principally after Robert Browning, with touches from several other eminent Victorians (e.g. William Morris's fascination with Northern mythology); Christabel recalls Christina Rossetti. The gradual discovery of the two poets' secret relationship roughly mirrors George McLean Harper's reconstruction of Wordsworth's youthful love for Annette Vallon, but also owes something to the rumored passion of Rossetti for the married poet-painter W.B. Scott.

But such is the power of Byatt's dossier -- excerpts from the standard Ash biography, "The Great Ventriloquist"; feminist articles about LaMotte; even a footnote referring to a disparaging essay on Ash by F.R. Leavis -- that a reader easily surrenders to the fancy that these two surely existed. They burn with such fire on the page as they speak of poetry, mythology, the condition of women, geology, evolution, spiritualism, love. Surely we overslept that day when Professor Altick lectured on them in English 401: Victorian Poetry; and no doubt Phyllis Rose really ought to have included a chapter on Ash and Ellen in her "Parallel Lives: Five Victorian Marriages."

All this may sound like post-Nabokovian playfulness: inventive and inconsequential, but it isn't. Byatt, a former British academic as well as a novelist, aims to show how some literary professionals, obsessed with textual questions, Lacanian psychology or deconstruction, may blind themselves to the sheerly human, the actual feelings, in poems: They get the meaning and miss the poetry. Sometimes they even miss the meaning. In "Possession" the modern-day academics prove figures of fun, but never R.H. Ash and his Christabel. Their love is so incandescent, so right, that a reader hopes against hope for these two appealing, intelligent, doomed, long-dead people. "He remembered most, when it was over, when time had run out, a day they had spent in a place called the Boggle Hole, where they had gone because they liked the word ..."

But further mysteries abound in "Possession." Maud and Roland, unknowingly, also visit the Boggle Hole, just for the fun of it. Maud and Christabel both buy the same kind of brooch. Parallels and echoes proliferate. Is there a supernatural affinity between the two poets and the two researchers? R.H. Ash once wrote to his wife, "If there is a subject that is my own ... as a writer I mean, it is the persistent shape-shifting life of things long-dead but not vanished." As in some mythic ritual, the past seems to be repeating itself. But to what end?

Two love affairs -- one Victorian and doomed, another contemporary and uncertain -- thus make up the magnetic poles of "Possession," but around these swirl wonderful subordinate characters. Blanche Glover, the desperate painter with whom Christabel has established a little civilization a deux. The baffling Ellen Ash. The young Breton Sophie who dreams of becoming a writer and duly records a troubling visit from her English cousin Christabel. The phony medium Hella Lees, who inspires Ash to violence and to compose his satiric monologue "Mummy Possest." Each shares a rough counterpart in the present: the spinster Beatrice Nest, who is editing Ellen Ash's journals; Val, Roland's depressed lover; Leonora Stern, the American feminist critic, at once gaudy, vulgar, bawdy and brilliant.

Naturally, Byatt also rings the changes on her meaning-laden title. Mortimer Cropper, custodian of the Stant Collection at the University of New Mexico, vows to possess every scrap of Ashiana. His rival James Blackadder will never quite let go of his great edition of Ash. Crusty Sir George Bailey hoards his manuscript treasures. Maud and Roland are both caught up in their quest for the truth, but also, it would seem, spiritually possessed by forces beyond their ken.

Throughout her romance, Byatt interweaves leitmotifs -- key words, recurrent allusions, names -- that gradually take on increasing significance: fountains, thresholds, the sunken world of Is, electric shocks, pale-golden hair, serpents, images of fire and whiteness, the fairy Melusina. With these she plaits together poems, lives and scholarship. As the book proceeds the achievements of Ash and LaMotte grow clearer, more personal, increasingly powerful. Appropriately one of the novel's climaxes leads to the proper reading of a poem and the discovery of a poetic vocation.

"Possession" is in every way an altogether magical performance, a prodigious act of literary ventriloquism. Still the last words here must be those of Randolph Henry Ash to his Christabel:

"I shall forget nothing of what has passed. I have not a forgetting nature. (Forgiving is no longer the question, between us, is it?) You may be assured I shall retain every least word, written or spoken and all other things too, in the hard wax of my stubborn memory. Every little thing, do you mark, everything. If you burn these {letters}, they shall have an afterlife in my memory, as long as I shall live, like the after-trace of a spent rocket on the gazing retina. I cannot believe that you will burn them. I cannot believe that you will not."

What a love story! What a book!

Michael Dirda is a writer and editor for Book World.