The idea behind the new shoot-'em-up "Posse" is a good one and couldn't seem more timely — exploring the black experience on the Western frontier.

After all, there were many black cowboys and their stories have never been told on film.

So it is all the more unfortunate that "Posse" doesn't tell its story very well — and in places is downright irritating.

Director/star Mario Van Peebles falls down by imposing his own florid directing style with such flourish that it overwhelms the material, not to mention his formidable cast. There are moments when the film is so chaotic that it feels like it's going to simply melt down, like one of the lead character's golden bullets.

"Posse" begins perfectly, however, with 80-year-old Woody Strode, whose considerable screen presence (which has not faded with time) dominated a number of Westerns in the '50s and '60s, most notably "Sergeant Rutledge." (A clip of Strode from "Once Upon a Time in the West" shows up under the end credits.)

Strode is used as a framing device, talking to a pair of modern reporters ("House Party" filmmaking brothers Warrington and Reginald Hudlin, in an in-joke cameo) about an Old West outlaw named Jesse Lee (Van Peebles).

As the film unfolds we meet Lee and his "Posse," composed of fellow Army deserters (Stephen Baldwin, Charles Lane and Tiny Lister Jr.) on the run after their corrupt commanding officer, Col. Graham (Billy Zane), has them steal a cache of gold and then orders them killed.

Lee is the silent leader, very much a Clint Eastwood type who is, naturally, out for revenge. He suffers from flashbackitis as he heads for a settlement called Freemanville, which was established by his late father.

In hot pursuit, of course, is Col. Graham — and if that's not enough, there are plenty more villains near Freemanville, led by evil sheriff Richard Jordan.

To attract young audiences, Van Peebles has included in the cast rap stars Big Daddy Kane and Tone Loc, who acquit themselves here nicely. And he invests a built-in sense of black cinematic history by dotting the cast with veteran favorites like Robert Hooks, Isaac Hayes, Pam Grier and his father, independent filmmaker Melvin Van Peebles. Unfortunately, most of them are little more than faces in the crowd.

"Posse" gets too preachy in places and it borrows from so many other Westerns for visual imagery — everything from "High Plains Drifter" to "Blazing Saddles" — that one wonders where "homage" leaves off and "rip-off" begins. (Would you believe there's even that old horror cliche — the killer who won't die — at the end?)

But the biggest disappointment here is Van Peebles' need to indulge his own worst instincts. The film is veritable fountain of how to sabotage your own narrative. There are too many odd camera angles, a ridiculous number of sepia-toned silhouettes against sunsets, an overdose of black-and-white flashbacks and so many quick-cut edits that even an MTV addict could be made nervous.

The result is a stylized mess.

"Posse" earns its R rating with a steady stream of violence, profanity, nudity and sex.