THE BELL JAR-K-B Cerberus, K-B Janus.

Sylvia Plath's life was so painful that she gassed herself in 1963 at the age of 31, but her posthumous career has been triumphant. Her subjects and sensitivity made her work special to a later audience that, unlike her contemporaries, could quickly recognize the ironies of her 1950s conflicts between being a woman and being a poet.

It therefore seems especially cruel to kill her off again, by reputation, in the movie version of her novel, "The Bell Jar." Undoubtedly this was not the intention of those who filmed her popular, autobiographical book.But for anyone who has not been familiar with her work, if firmly establishes the heroine with whom she is identified as being an elitist hysteric.

Esther Greenwood, in Plath's novel, is a talented poet, recognized as such at her New England college and at a New York magazine where she's a summer college editor, and beloved by a nice oung man. But the outside world, which she depicts with strangely deft satire, is distorted for her as if she were trapped in a bell jar. Much of this is now recognized as the craziness of the "feminine mystique" at its height.

In the book, this craziness logically drives her to madness and suicide.

But another distortion has taken place in the film. The outside world is shown as merely prosiac. Those around Esther seem reasonable and well-inentioned. Her mother, gently played by Julie Harris, is all winning simplicity. Her beau, played by Jameson Parker, is a trifle dull, but unselfishly devoted. Even her editor, as played by Barbara barrie, makes tough sense when she attempts to guide her work in a practical way.

Esther pounds each one with hatred. Marilyn Hassett, looking like a young Janet Leigh, tosses her long blond hair at each and sneers until, still not satisfied, she switches to screaming instead. The audience, instead of seeing the world from her point of view, peers from a sane world into the bell jar at this distorted creature knocking herself senseless against the glass.

What are her grievances? Her mother can't pay for keeping a horse at school, like the other girls. Her beau, who attempts to sympathize with her career, refuses to jeopardize his by canceling a crucial appointment to answer her midnight call for company. Her editor, instead of worshiping her for dropping the name of James Joyce, suggests that she make her work for the magazine comprehensible to its audience. Actually, all of her supposed intellectual activity seems pretentious, down to her cry of madenss, "I am! I and I am!" No doubt she felt she only had to give half the quotation, but it's a wonder she didn't give it in French.

Her dislike of sex applies so evenly to men and women, friends and strangers, that one can only conclude that she simply prefers narcissism.

Even the crazy pressures now obvious to feminists are made to seem petty. Many statements are made now ring the going - her mother suggesting that she learn shorthand, her beau suggesting that she can write poetry after marriage "when the kids are in bed." But they are made in ignorance, with such good intentions that one sympathizes when the mother complains, "I wish somebody would tell me when I do wrong." One feels that Esther need only have explained her complaint to change these sweet people, but that she did not deign to try.

The word for this behavior is not "sensitive"; it is "spoiled."