Only Ignorance Can Keep Her a Prisoner : THE HOUSE OF FORGETTING by Benjamin Alire Saenz; HarperCollins; $24, 341 pages

In this new novel Thomas Blacker, a prominent scholar at the University of Chicago known for his conservative, even elitist, critiques of American culture, is found stabbed in his home. His assailant has waited for the police to come--in no small part because all the doors of the Blacker mansion have been locked from the outside.

The assailant is a woman, dark and exotic-looking and stubbornly mute. Blacker, in his hospital bed, thinks of her as “Claudia.” The woman, in her jail cell, refusing to respond to interrogation by police Lt. Alexander Murphy, thinks of herself as Gloria Erlinda Santos. Blacker has been a widower for 25 years; none of his friends have ever seen the woman before.

But Blacker and Santos are hardly strangers. She tells her story, finally, to Jenny Richard, her court-appointed lawyer. Blacker kidnapped her from an El Paso barrio when she was 7, drugged her and drove her north. For the 23 years before the stabbing, she was his prisoner in a basement room--sometimes shackled and beaten; sometimes pampered with fine wines, food and books. When she turned 18, Blacker made her his concubine.

This story, if it gets out, will destroy Blacker’s career, but Blacker has powerful friends. Murphy, investigating more conscientiously than his superiors like, is removed from the case. Key pieces of evidence--Blacker’s journals, the car he drove to El Paso--disappear. Richard, too, is subject to intimidation. Goons hurt her dog and beat up one of her friends. She and Murphy, old antagonists, become allies out of necessity.

The case seems simple enough to Herold Burns, Chicago’s top criminal lawyer and a former Blacker protege. Santos must be pressured into keeping silent about her imprisonment. In return, she won’t be prosecuted for the stabbing, and she will inherit a fortune from Blacker, who has terminal cancer.

Blacker, however, has never been quite the man Burns and his other admirers imagined him to be. Recovering from the knife wound with surprising speed, he pursues his own, more twisted agenda: He wants Santos back.

As for Santos, after her unique experience of cruelty and indulgence, outward passivity and secret resistance, sophisticated learning and near-total ignorance of the world--what does she want? Can she even hope to figure that out?

Benjamin Alire Saenz, who has written two previous works of fiction, “Carry Me Like Water” and “Flowers for the Broken,” and two volumes of poetry, “Dark and Perfect Angels” and “Calendar of Dust,” clearly intends to do more here than write an ordinary crime novel.

He throws himself with gusto--and with a romantic, breathless style--into a probe of the kidnapping’s causes and effects. Why would a man like Blacker, who sets such store by civilization and refinement, do such a gross, uncivilized thing? And what kind of person would Santos be after a lifetime in a gilded cage?

With Blacker, Saenz fails to create a believable character of dimension, even though we get to enter the man’s mind now and then, and read excerpts from his journals. He’s pure creep, unlike the title character in John Fowles’ “The Collector,” whose disconcerting humanity had us rooting for him half the time. Blacker isn’t even convincing as an intellectual--we’re on Saul Bellow’s Chicago turf here, and the difference shows.

With Santos, Saenz succeeds in part. “The House of Forgetting” has moments when he does seem to intuit her state of mind. When Richard takes her to the top of the John Hancock Building, Santos is overwhelmed by “an ocean of blue” from the sky and Lake Michigan. “She felt something beginning in her--something for which she did not yet have a name.”

But elsewhere Santos seems insufficiently realized, despite Saenz’s best efforts. Rather than living and breathing, she remains an abstract concept of the author’s, part of a humorless parable of good and evil. For humor, and for most of the life in this novel, we have to rely on Murphy, Richard and their acquaintances--on the kind of gritty vitality that ordinary crime stories give us.