Brian De Palma is proof that being a great moviemaker doesn't necessarily entail being a great storyteller. Ever since his ascent in the Seventies as a kind of Hitchcock Lite, De Palma consistently does his best work when he isn't expected to make too much sense. But give the guy a big, juicy story to tell, and he winds up charred in a bonfire of his own bravado. The Black Dahlia, adapted from James Ellroy's acclaimed crime novel and involving perhaps the most infamous unsolved murder in California history, ought to thrill and amaze.

Sadly, it mainly just disappoints.

Set in post-World War II Los Angeles, the saga follows straight-arrow police officer Dwight "Bucky" Bleichert (Josh Hartnett), an ex-prizefighter who is paired up with another boxer-turned-cop, Lee Blanchard (Aaron Eckhart). The two become friends after an exhibition match to benefit the police department. Once Bucky meets Lee's sultry girlfriend, Kay (Scarlett Johansson), the three grow virtually inseparable.

The lives of the happy threesome are shattered the morning of Jan. 15, 1947, with a grisly discovery in a vacant lot downtown. The body of a young woman, Elizabeth Short, has been dissected in two, disemboweled and drained of blood. The grotesque piece de résistance: the killer has slashed the mouth from ear to ear, forming a clownish grin. Lee and Bucky are assigned to investigate the death of the woman who is nicknamed "Black Dahlia" by the L.A. tabloids.

So far, so good. What follows, however, is sheer incoherence. Lee suddenly becomes morbidly obsessed with the case, while Bucky meets up with Madeleine Linscott (Hilary Swank), a Dahlia lookalike who trolls lesbian clubs. A bargain-basement femme fatale with an accent to match, Madeleine hails from a rich and kooky family that seems airdropped from a David Lynch movie, replete with a Loony Tunes mother (Fiona Shaw) and naughty nymphet of a younger sister (Rachel Miner, updating Martha Vickers' character from The Big Sleep).

The deeper Bucky digs into the Dahlia mystery, the deeper the movie sinks into inscrutability. De Palma and screenwriter Josh Friedman are too enraptured by stylistic excess to streamline Ellroy's dense plot. Amid the period detail and De Palma's fluid camerawork, it is nearly impossible to catalog the mounting back stories of characters with whom we have only a glancing familiarity. This is no L.A. Confidential -- a far superior Ellroy adaptation -- much less Chinatown.

Mucking things further are wildly uneven performances. Hartnett is too much a blank-faced lightweight to generate much interest. Eckhart fares marginally better, but he looks positively Shakespearean next to Johansson, whose cleavage does most of her acting.

Still, De Palma is incapable of making a movie that isn't visually arresting, and he has a terrific collaborator in cinematographer Vilmos Zsigmond. The Black Dahlia is awash in period detail (with Bulgaria substituting for most of Forties-era L.A.) and the camera sweeps and soars with elegance, especially in a bravura one-take crane shot that sets the Elizabeth Short case in motion. And there is the requisite set piece involving murder on a staircase, a nifty bit of choreography that shows De Palma at the top of his game. The director also revisits some venerable themes of his -- voyeurism, pornography and the like -- but here they feel stranded, like jigsaw pieces to a puzzle that was forgotten long ago.

It's a shame. You sense what The Black Dahlia could have been in scenes where Bucky watches old audition reels featuring a sad and pathetic Elizabeth Short (a mesmerizing Mia Kirshner, with De Palma himself supplying the voice of the offscreen moviemaker). The images of the ghost woman are macabre and brim with spooky possibility. But then The Black Dahlia switches back to its absurdly complex story, and we return to a movie with more mysteries than clues.

Vilmos Zsigmond's atmospheric cinematography is beautifully presented in anamorphic widescreen 2.35:1. Clean and sharp, the picture quality is top-notch, devoid of glitches such as edge enhancement, noise or combing.

Like the image quality, the Dolby Digital 5.1 audio track is outstanding -- rich, dramatic and making creative use of immersive sound. I've got no complaints. French audio is available in 5.1 and Spanish is in Dolby 2.0.

Subtitles are available in English, Spanish and French.

Three solid featurettes by Laurent Bouzereau comprise the bonus material.

The 11-minute, six-second Reality and Fiction: The Story of the Black Dahlia details Elizabeth Short's infamous murder in 1947 and its subsequent reverberations throughout popular culture. Specifically, the piece explains why L.A. native James Ellroy, whose mother was slain in 1958 under mysterious circumstances, grew obsessed with the Short case. He says that Short began to merge in his mind with the loss of his mother "to explicate all the emotion that I never felt on the occasion of my mother's death."

The Case File (20:25) is a comprehensive making-of documentary featuring interviews with Ellroy, De Palma, Hartnett, Eckhart, Johansson, Swank, Kirshner, producer Rudy Cohen, producer Moshe Diament, writer Josh Friedman and more.

Finally, The De Palma Touch (Presented by Volkswagen) provides more insight into the creation of The Black Dahlia. While it purports to focus on De Palma, the featurette gives nearly equal time -- and justifiably so -- to Zsigmond and set designer Dante Ferretti. The featurette is 16 minutes, 53 seconds.

With a pedigree like Brian De Palma and James Ellroy, The Black Dahlia should've been a contender. No such luck. Despite the sumptuous visual feast we have come to expect from De Palma, a Byzantine screenplay with no end in sight makes this more L.A. Convoluted than L.A. Confidential.