Judith Rossner burrows deep into her second-row seat and tries to hide. There is popcorn, but she isn't hungry. For courage, she has stashed a bottle of wine under the seat.

A quarter of a million dollars and piece of the film - the deal her agent cut for movie rights to her novel "Looking for Mr. Goodbar" - is little comfort. As screening hour approaches, authors who sing away their creations to Hollywood come to feel like the father in the delivery room: They can't wait to see how things will turn out, but it's too late to make any changes.

Rossner, 42-year-old author of five novels, Bronx-born, brassy, divorced mother of two, waves the glossy program festooned with a langorous Diane Keaton in disco heaven. In "Goodbar," Woody Allen's endearing, foot-in-the-mouth girlfriend in "Annie Hall" plays Theresa Dunn, devoted teacher of deaf children by day, singles-bar devotee by night.

"They should put her on the cover of the paperback," Rossner is saying. "They have these giant sheds out in L.A. where they keep the books. Over the stacks of 'Goodbar,' they have a big sign, 'DO NOT SHRED.' I was taken there by this obnoxious paperback salesman named Arnie. Actually, his only sin was taking me to a cheap Hollywood restaurant for lunch . . ."

Rosner squeals. She spies actor Richard Kiley in the credits. "I LOVE Richard Kiley," she says. Three times, she says she loves him. Kiley plays Theresa's overbearing father, a stern Irish Catholic who trots around the house in a Notre Dame jacket and spits fire when his daughter moves into a place of her own. Kiley fawns over James (William Atherton), the upstanding social worker Theresa brings home for dinner; it delights him that James once studied for the priesthood.

The lights dim. As ". . . based on the novel by Judith Rossner" flashes on the screen, she sighs and shrinks lower in her seat. "It's one thing to be ready for it intellectually, but it's another thing to be here."

The movie rolls and, for the first time, Rossner sees how director Richard Brooks ("The Blackboard jungle," "Elmer Gantry," "In Cold Blood," etc.) has transformed Theresa. In the book, she was the after-hours thrill-seeker whose anti-gray, anti-black prejudices seem to make her at least partly liable for impending doom. In the film, Keaton plays a freedom-loving romantic whos bounces from man to man leave her the wounded doe. The victim. That, observes Rossner, is a weakness in the film. "She didn't do anything to provoke Tony (Richard Gere). In the book they set each other off." And the scenes of homosexual violence bring hisses from pockets of gays in the audience. The film has a somewhat macho tone.

Rossner covers her eyes; she nudges a neighbor; she fidgets in her seat. And when it is all over, she hungrily eyes the emergency exit. "I'd like to get out of here without having to talk to the producer" she says. "I feel like the mother who delivered her 13-year-old daughter to the door of Roman Polanski and didn't know what was going to happen."

The Producer. Freddie Fields. The former Humpty Dumpty of theatrical agents, who packaged such films as "Towering Inferno" and "Butch Cassidy and The Sundance Kid" before jumping into owning what was inside the package with "Lipstick" and now "Goodbar," is receiving handshakes at the top of the stairs. Rossner keeps her head down, passes within 10 feet of Fields without saying a word and plows onto Third Avenue. His face wears a cloak of gravity: He does not expect to see her. She was not invited, and learned of the screening only when a reporter with an extra ticket rang her up.

"To try and understand these Hollywood people is to flatter them," says Rossner, who didn't want to write the screenplay and kept her distance from the film, figuring it "was Richard Brooks' movie and he could do whatever he wanted. So word go out I hated it. What a joke! I just didn't want to intrude."

Rossner feel numb, "nauseated." No reflection on the film. She doesn't really know how she feels about it. "I don't know if it made me squirm because it was so different from the book or because it was bad. Objectivity was never my strong point."

Later, after two Courvoisiers in a West Side restaurant, Rossner confeses, "I hope it makes a lot of money." And she decides that Diane Keaton makes a convincing Theresa. Rossner is a fan. "She has that marvellous neurotic ambivalent self-hatred. She's very endearing. Not everyone who hates themself is lovable, but she is."

Rossner, in fact, claims to have recommended Keaton for the part. "The summer after he bought the movie, Freddie took me to lunch and asked, 'Do you have any ideas about casting?' I told him, well, my friend Dolores Karl, a banker with Morgan Guaranty Trust, says Diane Keation for Theresa. She's not sure she can play a straight role, but she's very funny and I have a feeling she'd be good. Fields dismissed it. The s.o.b. probably would deny it now. And I told him that my sister wanted William Atherton to play James . . .

"In the book, James is a lawyer. In the movie, he's crazy social worker. In theory, it was good casting. But it had some of the things I tried to get away from in the book, like pop sociology. You know, her father did this and therefore she turned out like that . . . It ain't that simple. But Keaton was very believable, wonderful, most of the time."