Grade: C-

Rule of cinematic thumb: when a character suddenly develops a hacking cough at the ninety-minute mark, the prognosis isn’t good, either for the afflicted person or for the movie. A perfect example is Robert Towne’s “Ask the Dust,” a labor of love that the veteran writer (and occasional director) has wanted to make for more than thirty years. It’s his own adaptation of a semi-autobiographical 1939 novel by John Fante, recounting the struggles of Fante’s surrogate, a chip-on-his-shoulder Italian-American named Arturo Bandini (played by Colin Farrell), to make it as a writer while living in a seedy hotel in L.A.’s Bunker Hill district during the Depression. His professional aspirations, nurtured from afar by H.L. Menken, alternate with complications in his personal life, which include romantic interludes with Vera (Idina Menzel), an aggressive but pathetic Jewish woman, and Camilla (Salma Hayek), a fiery Mexican waitress. Let’s just say that while Fante didn’t fare all that well himself–by the close of his life his books were largely forgotten, though they’ve enjoyed something like a renaissance since–his stand-in Bandini comes out of things better than either of the women in his life.

It’s not hard to see why Towne, who’s probably best known for penning “Chinatown” (still his best work, easily topping scripts for big-budget escapist fare like “Mission Impossible” and “Top Gun”), might have been drawn to the novel. Writers can sympathize with characters who are suffering writers themselves. But whatever the virtues of the original book, this movie is not only woefully old-fashioned but emotionally opaque, with characters that never come to life and told at a plodding pace that fails to generate the desired intensity. It’s especially blighted by the fact that in an excess of fidelity to his source, Towne resorts to having Bandini narrate the picture pretty much straight-through–a choice that merely accentuates the protagonist’s unattractive tendency to self-centeredness and self-pity. If a screenwriter can’t reveal a character’s inner life dramatically, without embracing such crutches, perhaps it’s a sign that a book shouldn’t be adapted at all.

But in this case it’s not just the writer’s choices that doom the finished product–it’s that the material itself doesn’t particularly engage us. Essentially all that happens over the course of two hours is that Bandini impresses on us, over and over again, how rough he has it trying to survive and prosper as an artist while he haltingly matures as a person through his difficult relationships, first with the doomed Vera and then with the flamboyantly take-no-prisoners Camilla, both of them in different ways social outcasts due to pervasive prejudice of one sort or another. (A major theme of the story is the intense anti-Mexican bigotry that was part and parcel of L.A. culture during the thirties.) But at least in this telling, the three lead characters remain resolutely one-dimensional, and though Farrell, Hayek and Menzel throw themselves into the roles, they never succeed in making Bandini, Camilla and Vera seem like real human beings. Instead, they’re nothing more than symbols or types–abstractions rather than authentic individuals–and the actors, in their period garb (or, in a couple of cases, tossing it aside), remain what they are–modern people play-acting in old clothes, pretending to be personalities from a different era, like students in a woebegone historical pageant.

It doesn’t help that the only other figure of consequence is Hellfrick (Donald Sutherland), a worn-out alcoholic who loves across the hall from Bandini; Sutherland’s fine in the part, but his presence merely serves to remind us of a more interesting movie about 1930s L.A., John Schlesinger’s 1975 adaptation of Nathaniel West’s “The Day of the Locust,” in which he played Homer. That picture had its own problems, but its grotesqueness was at least riveting, even though it might make you feel that you were observing a particularly gruesome accident. “Ask the Dust,” on the other hand, makes you feel nothing at all, unless boredom counts.

Aside from these four characters, one will briefly notice Sammy (Justin Kirk), a strange bartender at the dive where Camilla works and, it appears, her sometime lover, and Mrs. Hargraves (Eileen Atkins), the snootily aloof owner of the hotel where Bandini lives. Neither is more than a stick figure, nor is either very well played. Then there’s the voice of Menken, provided, oddly enough, by film critic and historian Richard Schikel, whose flat line readings demonstrate than that while he might be a serviceable narrator for documentaries, he’s certainly no actor.

From the technical perspective “Ask the Dust” is pretty extraordinary. It was actually shot on a modest budget in South Africa, where production designer Dennis Gassner, art directors Richard Johnson and Tom Hannam and set decorator Nancy Haigh fashioned a bit of 1930s L.A., and the characters are fitted out with dead-on costumes by Albert Wolsky. The effect, as captured impeccably by cinematographer Caleb Deschanel, is very evocative though hardly “realistic.”But it only makes the film feel even more like a hopeless throwback: it even apes the movies of seven decades ago in its title sequence (in which the credits are given on a book’s turning pages). Ultimately the film is likely to strike you all too strongly as something made from a musty script written a long time ago and now taken out of the drawer and treated more as a revered artifact than a springboard for enlightening drama. Towne’s long-gestating passion for Fante’s book has resulted in an emotionally parched picture; for all his desire to recapture the vibrancy of old-fashioned tales of art and love, “Ask the Dust” is as arid as its title.