Vivid visuals in an otherwise sparkleless 'Hammett'

Hammett is the first American film by the celebrated West German director Wim Wenders. It did not come easily. For years, Hollywood scuttlebutt gave hints of script problems, indecision about the plot, and disagreements between Wenders and executive producer Francis Ford Coppola.

Finally on the screen, ''Hammett'' turns out to be better than expected, although still below the standard of Wenders's best work. In all, a respectable but minor movie.

The story is a fictional yarn based on the life and ideas of detective-turned-author Dashiell Hammett. He's shown as a pulp writer who wants to be left alone with his typewriter. But an old crony shows up, needing help with a criminal case. The plot thickens by the minute, until half of San Francisco - from the loftiest leaders to the lowest dregs - seems to be involved.

Someone should have given ''Hammett'' the kind of dialogue that sparked a real Hammett novel like ''The Thin Man'' instead of the choppy, talky lines that Wenders wrestles with here. The plot is also trivial, from its trite beginning to its contrived resolution, which has something to do with blackmail and sexual secrets in high places. And the star, Frederick Forrest, brings little charisma to his role.

What makes ''Hammett'' watchable despite all this? Its strong sense of visual detail, and its insinuating rhythm. In all his major films, Wenders approaches fiction as if he were documenting reality. He loves to focus on the way things look, feel, and work, even if this means letting the story wait for a while. The best parts of ''Hammett'' are the interludes when the hero's clacking typewriter fills the screen in long, meticulously photographed shots. Nothing happens during these moments, but they look just great, and there's something charming about their very arbitrariness.

Other assets include some good supporting performances, including an appearance by Jack Nance, recalling his memorable work in ''Eraserhead'' a few years ago.