Shana Alexander believes that Jean Harris is innocent of murder in the killing of her longtime lover, Dr. Herman Tarnower, and she makes a persuasive case for that belief. She further believes that Harris would have been exonerated of the crime had she not placed so many restrictions on her own defense, and had that defense been more systematically mounted, and she makes a persuasive case for this belief as well.

For crime buffs, and/or Harris-Tarnower buffs, these arguments will be sufficient reason to read "Very Much a Lady," Alexander's account of the relationship between the headmistress of the Madeira School and the Scarsdale Diet doctor. But her book is, in point of fact, quite a lot more than a competent unraveling of a complicated case. It is also a sensitive portrait of Jean Harris, who emerges as a vastly more interesting and sympathetic human being in Alexander's hands than she did in those of Diana Trilling, in her 1981 book about the scandal, "Mrs. Harris."

Doubtless this has more than a little to do with the friendship that developed between author and subject as Alexander went about her researches, in which Harris cooperated fully--though without placing any restrictions on Alexander's freedom to tell the truth as she understands it to be. But the really important point is that Alexander has clearly tried to be absolutely honest: to Harris, to herself, to the reader. She has written an abundantly sympathetic book, but in no way is it a fawning one; it is precisely because she gives us Harris, warts and all, that Harris appears, for the first time, as someone genuinely worth caring about.

Alexander's portrait of Harris has three key elements, all of which should be familiar to anyone who followed the case but none of which has been so meticulously explicated elsewhere.

The first is that, like so many American women of her generation (she was born in 1923), Harris was raised to be "a good girl"; this put her under powerful internal and external pressure to conform to the standards set by polite society, and thus subjected her to great spasms of guilt when she violated them.

The second is that she suffered from deep feelings of inferiority toward the high society whose daughters she educated in loco parentis; she was "blind to her own worth," which in fact was quite considerable, and was highly dependent on the good opinion of others.

The third, closely related to the first two, is that the "modern" romance of Harris and Tarnower exposed her to terrible doubts and strains: "It cannot have been easy for Jean Harris to play the part of Herman Tarnower's modern liberated woman, let alone to be a mistress."

Her portrait of Tarnower is no less interesting, though it is almost entirely unforgiving. He emerges as a society doctor whose special talent was to stroke the egos of a wealthy clientele, a lady-killer whose "very aloofness" was part of his strange appeal, a ceaseless striver after "authority, dominion, control," and a medical practitioner of highly suspect abilities. She quotes a young woman who had been a guest at one of his lavish dinner parties:

"You'd have to spend an entire evening looking at his scrapbook and hearing about all the awards he'd received . . . Then came all the descriptions of his hunting expeditions, and you'd have to admire all the trophies on the wall. The food was ghastly--not distinguished, just fancy, and the doctor had no small talk. He never smiled. He had no wit. He had no subject matter but Dr. Tarnower. To him, money equaled class. He constantly talked about how much things cost, how much land people had, how much money. He would speak of his friends as 'my friend Joe Cullman, chairman of the board of Philip Morris,' or 'my friend John Loeb, president of Loeb Rhoades.' Once he even said, 'My friend, Chou En-lai.' "

A loathsome creature in virtually all respects, and how it is that Jean Harris loved him so passionately is a true mystery of the human heart. But love him she did, and apparently love him she still does. In a letter from prison to "a friend," presumably Alexander, she wrote: "Without feeling the slightest bit morbid I can wish that I were gone and he were alive." Writing from prison to a "visitor," again presumably Alexander, she said of her failed attempt at suicide in Tarnower's bedroom: "Essentially I did commit suicide that night. I just did it the hard way--which seems to be my modus operandi."

More than anyone else who has written about it, Alexander understands that for this reason the story of Jean Harris is poignant and meaningful. Few things, after all, can more arouse our sympathy than an unrequited flame that refuses against all the evidence to be extinguished, and few things can say more about the capacity of the heart for blind, naive, trusting devotion. Jean Harris may or may not have been a fool, but she most certainly was a real human being; that alone is quite enough to make her matter to us.

"Very Much a Lady" is a good work: balanced, skeptical, worldly, compassionate. Alexander's prose lapses occasionally into stickiness ("these moments were little oases of companionship and closeness in the vast desert wastes of her solitude"), but for the most part it is as forthright as her subject deserves. She persuaded a great many people to talk to her; they did so both interestingly and revealingly. She believes that what she has to say is worth listening to, and she is right, but she says it without pretense--which no doubt is yet another reason why her account is so arresting and persuasive.