When people discuss maverick director Quentin Tarantino's films, they rarely use the words "understated violence." Then again, his movies have never been accused of being boring, either.

But fans and critics alike may be using both terms after seeing "Jackie Brown," Tarantino's adaptation of the Elmore Leonard novel "Rum Punch." This sluggish comedic thriller is a huge disappointment, especially as a followup to "Pulp Fiction."

And though it is much less violent than Tarantino's customary fare, "Jackie Brown" is still filled with the profane language, vulgar talk and nonstop use of racial epithets that he's become famous for.

Conceived as a star vehicle for former "blaxploitation" actress Pam Grier, the movie takes 150 minutes to tell what should have been a 90-minute story. Without the surprisingly strong co-starring turn by veteran character actor Robert Forster, it might have been an even bigger dud.

Grier stars as the title character, a disgraced flight attendant in her 40s who's been forced to smuggle cash into the United Statets for illegal arms dealer Ordell Robbie (Samuel L. Jackson), just to make ends meet. But after one of her "cash runs" to Mexico, Jackie is busted by ATF agent Ray Nicolette (Michael Keaton) and LAPD detective Mark Dargus (Michael Bowen).

Threatening her with a lengthy prison sentence, the two investigators put pressure on Jackie to testify against her gunrunner boss. Ordell, though, persuades her to keep cool, while secretly hatching a plan to kill her if it looks like she might bring him down.

What neither Ordell nor the detectives know is that Jackie is actually "playing" each side against the other. With help from sympathetic bailbondsman Max Cherry (Forster), she hatches a plan to retrieve Ordell's illegal cash stash for herself and give the detectives enough evidence to bust him.

Actually, a good film editor could have made this flabby mess much better. Tarantino draws some scenes out needlessly (he lets the action be dictated by songs on the soundtrack rather than common sense or pacing).

There's also a distracting side story about Ordell's pot-smoking girlfriend (Bridget Fonda) and his just-released convict pal (Robert De Niro) that exists only for the sake of a punchline, and not a very funny one at that. Considering the uninspired performance by De Niro, these scenes could have been cut out completely.

As mentioned, only Forster seems to be having much fun. He's fabulous, even when his fellow performers are not. Jackson, in particular, plays Ordell a little too familiarly (he sounds exactly like Jules from "Pulp Fiction," with a different haircut). And even though she's obviously meant to be the focus of the piece, Grier isn't given nearly enough to do.

"Jackie Brown" is rated R for almost nonstop profanities and use of racial epithets, violence, drug use, sex, vulgar references and some brief partial nudity.