"Overnight" is unapologetically a cautionary tale, but exactly what it's cautioning us against is not always apparent.

A fly-on-the-wall documentary that chronicles an abortive directing career, "Overnight" is compelling in a train-wreck kind of way. It details how Troy Duffy's abrasive, unyielding personality caused the wheels to fall off one of the most publicized movie deals of recent years.

That was the 1997 arrangement Duffy, then a 25-year-old bartender, made with Harvey Weinstein and Miramax. Not only would they finance "The Boondock Saints," a violent action film Duffy would write, direct and produce the soundtrack for, they would buy J. Sloan's, the Melrose Avenue bar he worked at, and give it to the filmmaker. No wonder USA Today put the story on the front page, and no wonder Duffy himself wrote on a copy of the Hollywood Reporter he sent home, "I shook up the world, Ma."

Mark Brian Smith and Tony Montana, "Overnight's" co-producer-directors, were already part of Duffy's entourage and working on a documentary about him when the deal went down. So they had access not only to insider meetings and phone conversations, but also to the tirades, the fulminations, the grandiose pronouncements that were part of Duffy's MO.

Profane, voluble, unflinchingly candid, his impossible-to-intimidate personality was in truth a documentarian's dream. A self-mythologizer who believes he's right 100% of the time, Duffy was untroubled by modesty. Especially after Miramax came into the picture.

"We're going to accomplish something no one in the world has ever done, be accepted on a huge scale in both mediums, film and music," ran a typical Duffy declaration. Referring to a group of bandmates and pals who called themselves the Syndicate, Duffy claimed "this group I believe has more potential to put more creativity on the table than probably any seven men in the history of this town."

At first everything went well. Duffy's band, the Brood, signed a deal with Maverick Records without so much as an audition. And Duffy himself, after fulminating against the likes of Keanu Reeves and Ethan Hawke ("a talentless fool"), has casting meetings in the bar with an impressive collection of actors: Mark Wahlberg, Billy Zane, Emilio Estevez, Patrick Swayze, Matthew Modine, Vincent D'Onofrio. There are even phone messages from Kenneth Branagh, and an unfilmed encounter with Ewan McGregor.

Gradually but unavoidably, things begin to go wrong. Because "Overnight" is filmed almost exclusively from Duffy's point of view, with no one from Miramax willing or able to go on camera, we don't know the problems exactly. But as Miramax puts "Boondock" into turnaround and Maverick drops the record contract, we can only assume Duffy's personality problems outstripped what he called his "deep cesspool of creativity."

Bruised and battered, Duffy and his team persevered and found new backers. Financed by Elie Samaha's Franchise Pictures, "Boondock" eventually was made with a cast including Billy Connolly and Willem Dafoe, but it sank on its release. The Brood's record came out on another label and did even worse. Through it all, Duffy was unchanged, alienating everyone in his path and feeling underappreciated by his entourage.

But though "Overnight" seems to be cautioning us about the excesses of filmmaker ego, it isn't always consistent. The film seems to buy into Duffy's notion that "Boondock's" difficulty finding a distributor can be chalked up to a vendetta on Weinstein's part, even though any company that smelled a healthy profit wouldn't have bothered about what Miramax's leader felt. A more likely reality is that, the man's personality being what it is, companies were simply leery of getting into the Troy Duffy business.

What "Overnight" is really cautioning us against, though it's not clear that it knows this, is the movie business in general and the indie-film world in particular. It's an unacknowledged indictment of a system of agents, managers, hangers-on and production executives that automatically equates arrogance and bad-boy behavior with bottomless talent, no questions asked — that tolerates, feeds on, even encourages characters like Duffy. What's noteworthy about "Overnight" is not that Troy Duffy failed but that he came so close to succeeding.

'Overnight'

MPAA rating: R, for pervasive strong language, sexual references and some nudity

Times guidelines: Considerable profanity, a glimpse of nudity

A Black & White Pictures presentation, in association with Ronnoco Productions and Ether Films, released by THINKfilm. Directors Mark Brian Smith & Tony Montana. Producers Mark Brian Smith & Tony Montana. Executive producer Tony Montana. Cinematographer Mark Brian Smith. Editors Tony Montana, Mark Brian Smith. Running time: 1 hour, 21 minutes. In limited release.