American Gun. It's hard for a film to begin with a more auspicious title and subject, but almost as hard to be able to follow up that initial promise with something worthy. Aric Arvelino's assured debut take a number of different storylines, all revolving in some fashion around gun violence, its cause and effects, and tries to spin them into an evocative tapestry that will hopefully in the end have something to say about where we as a country stand on the matter. The individual bits, however, are much better than the whole.

In the most dramatic and difficult-to-watch story, Marcia Gay Harden plays Janet, a single mother and factory worker in Oregon, haunted by violence. Three years before, her older son was one of two teenagers who enacted a Columbine-style massacre/suicide at their high school. Now she's a wreck, sleeping with a random succession of losers while her other son goes to a private school she can't afford, leading her to sell her story to a tabloid news show whose interviewer reminds Janet on camera that her younger son, David (Christopher Marquette), is now the same age her other son was when he went on the shooting spree. "Does that frighten you?"

As the massacre's third anniversary stirs up old problems in Janet's Oregon town, the issue of guns crops up in two ways at a high school in a rough patch of Chicago's South Side. Jay (Arlen Escarpeta) is the rare teenager with promise, working long night shifts at a gas station and acing his classes-but still he carries a gun, for protection from all the local hoods, that he leaves in a grate outside the school every morning. The principal, Carl (Forest Whitaker), is a powerful voice of authority, practically the only thing holding the crumbling institution together-even though it means his wife and young son suffer from the lack of attention-and fighting constantly to keep guns and any sort of violence out of his school. Jay and Carl's paths collide when Jay is caught with the gun and threatened with expulsion.

The third and most puzzling plot-string is set in Charlottesville, South Carolina, where Mary Ann (Linda Cardellini) is attending university and helping out at the gun shop owned and operated by her grandfather (Donald Sutherland). Mary Ann is uncomfortable working at the shop, a tension her grandfather reads as something more personal. Eventually, something will happen that makes her take a much more vested interest in firearms.

Given his subject matter, one can understand why director/co-writer Arvelino would set his framing story in a gun shop, especially one run by a gentle old man. The idea appears to be to show the deceiving tranquility of the industry, that for all the death and destruction wreaked by firearms across the country, many of them are sold out of cozy old family-run places that are about as threatening to behold as a bait shop. It's an interesting gambit, but one that doesn't play out well in practice, given the story's almost complete lack of dramatic tension.

The film is more successful when it moves back to Oregon and Chicago. Harden has practically perfected the art of playing beaten-down women on the brink, and it serves her well here in an unsympathetic role that emerges as the film's single most vivid element. Watching Janet being knocked back and forth between the scorn of her neighbors (blaming her for not seeing warning signs with her dead son) and David (begging her to let them move away so he can forge a new life somewhere) is a wrenching thing; she's trapped in a past she still can't comprehend, and unable to see her way forward. Whitaker also plays to his strengths, finding the wounded soul buried inside a man whose job requires he present only strength and fortitude to the world. He's a totemic figure slowly collapsing under the burden of maintaining his school-one hears the faintest tremor in his secretary's voice when she suspects he's thinking of leaving.

Arvelino has come up with two-thirds of a good movie here, even if it seems more suited to an hour-long television drama than a feature film. While it's commendable that he felt no need to unite every element of his film-one of the stories ends utterly inconclusively, and none is entirely resolved-American Gun seems more like talking points for a film than a finished product. The effects of violence and the gun trade are examined, but little light is shed.

-Chris Barsanti