Mary Pacios is no writer. She's not a detective, either, but she was driven to become both by what she calls the "lies" surrounding the murder of her childhood friend, Elizabeth Short, aka the Black Dahlia, one of the sexiest victims never to leave Hollywood alive. The two saw 25-cent flicks and drank malteds together during World War II in Medford, Mass.

Pacios was 12 years old when her friend's body was discovered on Jan. 15, 1947, in Tinseltown, where the 22-year-old Short had gone to fulfill her dream of becoming an actress. Short had rope burns on her wrists, cigarettes burned into her breasts, her head had been beaten in and her mouth had been cut from cheek to cheek. The killer then had bisected her body just above the navel and left the two halves in a vacant lot.

Many people still know about the Black Dahlia (so-called because of Short's pale white skin, red red lips and the black bouffant hairstyle that framed her face). There are books and movies, a computer role-playing game and several Web sites devoted to a murder that remains unsolved. Probably the most famous version of the killing is in James Ellroy's 1984 novel "The Black Dahlia."

It's that fictionalization that Pacios, 66, says motivated her to snoop and write. An artist for most of her life, Pacios had painted Short, but not written about her. It wasn't until 1987 that she was inspired to correct certain "misperceptions" -- that Short was a victim no one would miss, a Hollywood whore who got what she deserved.

The most compelling parts of "Childhood Shadows" are interviews with old-time newspaper reporters and Pacios' own family. It may be Pacios' non-writer instincts that let her concentrate on the context of the murder rather than just the gruesome details.

That's not to say she doesn't get into those, too. Pacios, like many of us, is fascinated by what was done to Short's body. She chimes in with her own suspect, too: Orson Welles. That's right. She believes the actor-director had a kind of mental illness called diphasic personality that channeled creative frustration into aggression.

Her evidence includes strange incidents taken out of Welles biographies. And, most compelling for her, photos of a carnival funhouse set for "The Lady From Shanghai" designed and constructed by Welles. Unused in the movie, it was decorated with female body parts, a mannequin face mutilated like Short's and a woman's body cut in half.

Although she used to live in the San Francisco Bay Area -- where Elizabeth "Bette" Short is buried -- Pacios now lives in Wyoming. She returned to San Francisco recently for a mini book tour before heading off to Denver in September for Bouchercon 2000, the 31st World Mystery Convention, where she'll sit on a panel called "Fact, Fiction and Fictionalization."

I attended her reading at a San Francisco bookstore. Her friends there seemed a little preoccupied with my presence, mostly, I think, because she's already been attacked by some reporters for maligning Welles. Dressed in a dark blouse and brown leather pants, Pacios seemed comfortable in her new role as writer and read thoughtfully, her East Coast accent tweaking slightly in my West Coast ears.

You said that part of sitting on this mystery writers panel is that you wanted to help draw the line between fact and fiction, and you said true crime is supposed to do a service. What did you mean by that?

Shed light. OK, the panel is "Fact, Fiction and Fictionalization." And I feel, either do fact or do fiction, and if you're going to fictionalize, you muddy, you throw the crime back into darkness. Whereas, if you take a true crime like the Black Dahlia, and you really try to be honest about the time, try to reveal the time, try to say what's going on -- be factual.

Facts can be more compelling than what anyone could possibly dream up, I believe. But when you fictionalize, you're distorting. It's your fantasies. Why not just do fiction? Just make up a crime. Just do outright fiction if you want to fantasize. Do you see my intentions? Do one or the other. Don't fictionalize a real crime, and that's my big beef with Ellroy. He caused a lot of hurt, harm for the [Short] family.

Because his ideas are the ones that people think about now?

Yeah, they think about that. Plus, he smeared the family. They were at one time thinking of suing him because of the way he portrayed Elizabeth Short as a runaway, and she wasn't. She came from a nice family.

Maya Angelou reads from "The Heart of a Woman"