Brian De Palma doesn't just know how to make a camera move, he can seduce it to do a sinuous dance. So The Black Dahlia looks and flows great, dripping with the 1940s crime-thriller atmosphere that James Ellroy described in his 1987 novel. On other levels — plot (overstuffed), suspense (muted), acting (Hilary Swank as a femme fatale? Please!), posing (Scarlett Johansson plays dress-up as a mini Lana Turner), sex (it's all before and after) — the movie is a bust. The setup is this: Two cops — Lee Blanchard (a strong Aaron Eckhart) and Bucky Bleichert (a hopeless Josh Hartnett) — become obsessed with the mutilation and murder of a let (Mia Kirshner). De Palma throws everything at the screen, but almost nothing sticks.