Before there were lurid tabloid TV murders, there were lurid tabloid newspaper murders, and one of the most notorious of the last century was the case of the Black Dahlia.

The gruesome slaying transfixed postwar Los Angeles the way the double homicides of Nicole Simpson and Ron Goldman did a generation later. It was film noir come to life, a glimpse into a shadow world of macabre kink and psychosis and corruption that ripped up the sunny postcards of suburban idylls and Hollywood dreams. It was the Manson murders before the invention of television.

On Jan. 15, 1947, the body of a stunningly beautiful, raven-haired would-be actress from a small town in Massachusetts was found in a vacant lot near Leimert Park. She was 22 years old, a troubled party girl named Elizabeth Short.

Children should stop reading now.

The corpse was nude, lying face up, spread-eagle, seemingly posed. The body had been cut in half above the hips. There were signs the dead victim had been sodomized, and other disturbing details that suggested a modern-day Jack the Ripper was loose.

The crime was splayed across the front pages for months -- fed in part by taunting notes sent by the alleged killer to the newspapers. It was horrible and evil, and the citizenry could not read enough about it. There have been hundreds, maybe thousands, of articles, a string of books, including a novel by crime writer James Ellroy, and movies and documentaries.

But the murder went unsolved.

Today, a retired veteran homicide detective from the Los Angeles Police Department claimed that he has cracked 56-year-old case. Steve Hodel, now a 61-year-old private investigator, has written a book on his researches, and he marshals a voluminous pile of evidence -- some damning, other bits a stretch.

The killer?

Hodel says the murderer was his father, a wealthy, dashing and politically plugged-in doctor and genius, who was also a sociopath and serial killer.

At a news conference in the Academy Room at the faded old Hollywood Roosevelt Hotel to promote his book, "Black Dahlia Avenger" (Arcade Publishing), released today, Hodel mounted the podium and first read a prepared statement and then, looking florid and nervous, took questions about his father.

Hodel began by saying his investigation was "my gift to L.A. and the LAPD," and descended into a description of his life turning into a hell of devastation and betrayal.

It is all very sick and slick and sad, and designed to sell books. But is it true?

It is impossible to know, skimming through the book and hearing Hodel's answers, if he has in fact solved the case of the Black Dahlia, so dubbed by the press because of Elizabeth Short's black hair and penchant for black attire.

But this is what Hodel claims, some facts confirmed and others to be judged: that his father was a high-flying physician who lived in a house designed by Frank Lloyd Wright, who ran a clinic treating venereal diseases, and so had amassed intimate dossiers of sexual lives of flatlander prostitutes and the high and mighty who lived in the Hollywood Hills.

In 1999 George Hodel Jr. died at age 91, and his wife gave to her son (a former cop) the doctor's "secret photo album" containing pictures of family and friends, and photographs of several unidentified young women.

Two, Hodel says, were pictures of Elizabeth Short, whom he recognized. He says he doesn't know why -- maybe from a glimpse of a 1975 documentary about the Black Dahlia case.

According to Hodel, his father was romantically involved with Short, and the lovers were seen together at a downtown hotel, which Hodel discovered through interviews and rummages through faded police and grand jury investigations.

Secondly, Hodel says, the dismembering was done by a trained surgeon. And finally, he argues, the notes sent to L.A. newspapers taunting the police -- one said "Catch me if you can" -- were in his father's handwriting, confirmed by forensic experts in script analysis.

Did the notes reveal intimate, unpublished details of the crime? They did not. After the murder, a dozen cranks and crazies confessed to the crime, but none was prosecuted. They were, instead, sent to mental institutions or ignored. Even if George Hodel penned the notes, could he have been just another nut or have had more insidious but still nonmurderous motives? Hodel could not say.

But the son says he discovered "secret grand jury hearings" that finger his father as "the prime suspect" in the Black Dahlia killing and another, the so-called "Red Lipstick Murder," in which the assailant scribbled "B.D." on another woman's corpse, that of bludgeoned Jeanne French.

It doesn't stop there.

Hodel suspects that his father, who fled to the Philippines in 1950, was a serial killer who might have slain 20 other women in L.A.

And abroad?

"I suspect there are many bodies in Asia," Hodel says.

And there is more: Hodel alleges a massive conspiracy and coverup in the LAPD, lest the doctor reveal his knowledge of police ties to prostitution, gangsterism, illegal abortion rings and on and on.

Still, this is not the first book to "solve" the Black Dahlia case. In her 1995 "Daddy Was the Black Dahlia Killer," Janice Knowlton claimed, based upon "repressed memories," that her father did the deed.

In the press packet, Hodel's publicist included a statement from Stephen Kay, Los Angeles County head deputy district attorney, who avows that he read through Hodel's evidence and manuscript and concludes: The case has "finally been solved."

Kay writes, "Based on the results of Steve's investigation, I would have no reservations about filing two counts of murder against Dr. George Hodel . . . and I have no doubt that his father not only murdered Elizabeth Short but also murdered Jeanne French less than one month after the Black Dahlia murder."

Now, it gets even spookier. Los Angeles Times columnist Steve Lopez, alerted to the book, visited the current L.A. County district attorney, Steve Cooley, who says, sure, we have a file on the case and grand jury documents -- have at it.

In today's L.A. Times, Lopez writes that as he sifted through the dusty box, out dropped a photograph of George Hodel, "his eyes dark and narrow." Lopez writes, "So he was a suspect." According to the files, Hodel was one of 22 suspects.

In another file, Lopez unearthed a transcript of an LAPD bugging of Hodel's house in 1950, just a few months before he absconded to Asia. (Hodel was also tried and acquitted of an incest charge around the same time.)

In the transcript, Lopez records that Hodel said, "Supposin' I did kill the Black Dahlia? They couldn't prove it now. They can't talk to my secretary because she's dead."

After his news conference, a question is put to Steve Hodel: Isn't this creepy that you're making money on a book that accuses your dead father of being a butcher?

He does not have a great answer. Well, he worked on the investigation, it could help the LAPD put old demons to rest, he should be paid for his hard work. Etc.

Hodel poses for a photographer, hoisting his book aloft, and . . . what? Smiling? Proud? Ashamed? Resigned?

Elizabeth Short was cut in half. Hodel says he has not spoken to her relatives.

The gruesome murder of Elizabeth Short, below, has gone unsolved since 1947, but retired LAPD homicide detective Steve Hodel, right, says he's cracked the case and reveals the killer in his book, "Black Dahlia Avenger."