Filmmaker John Sayles knows how to deliver the goods, and his latest ensemble effort, the complex, perceptive, character-driven melodrama "Lone Star," is no exception.

In fact, many national critics have called "Lone Star" Sayles' best film — which is high praise indeed when you consider that his filmography includes "The Secret of Roan Inish," "Matewan," "Passion Fish" and "Return of the Secaucus Seven," among others.

Considered the godfather of American independent cinema, Sayles is at his best when he's creating a group of fully-realized characters who come from different social or cultural strata and whose lives intersect due to some sort of dire circumstance, usually of their own making.

In this case, it's a 40-year-old murder mystery.

Sam Deeds (Chris Cooper), the sheriff of a small Texas border town, becomes obsessed with the case after a human skull is found on an abandoned military rifle range, along with a Masonic ring, a sheriff's badge and a pistol slug.

When the victim is determined to be Charley Wade (Kris Kristofferson), a corrupt, racist, ruthless former sheriff who disappeared 40 years earlier, Sam begins to wonder if his late father, Buddy (Matthew McConaughey), might not have been the killer.

Buddy succeeded Charley as sheriff, and Sam is constantly being compared to him, in none too glowing terms. In a way, Sam almost hopes Buddy is guilty.

Meanwhile, the town is torn by racial strife, as the Mexican, black and anglo residents have trouble seeing eye to eye on local politics. And now, the white minority is feeling threatened, as a shift in power toward the Mexican majority is in the wind.

The Charley-Buddy conflict is revealed slowly in flashbacks, while subplots include Sam rekindling his relationship with an old girlfriend, Pilar (Elizabeth Pena); Pilar's mother (Miriam Colon), who, for some reason, has strong resentment toward the young Mexicans who cross the border into Texas; the estrangement between the owner (Ron Canada) of the only black nightspot in town and his son (Joe Morton), the military commander of a base that is doomed to close; the town mayor (Clifton James), who seems to know more than he's telling about the night Charley Wade disappeared; etc.

These stories — and much more — are interwoven delicately into a larger tapestry, so that they seamlessly become one telling tale about life in a small town, where corruption is quiet and everyone knows too much about everyone else's business.

As Sam continues his investigation, the tapestry takes shape, and by the end, we feel like we have come to know everyone presented here. What's more, just when you think you've figured out the mystery — Sayles throws us for a loop with a climactic moment that is shocking as it is revealed, and devastating in its long-term implications.

"Lone Star" is indeed a rare film, one with the kind of texture that is all too uncommon in American movies these days. Sayles knows how to use the camera to stylistic effect, how to write sharp dialogue that adds spice to the story and how to get the best from his actors, all of whom excel in the three-dimensional characters he gives them. (Including Frances McDormand in a hilarious one-scene riff.)

The film is rated R for violence, sex, profanity and vulgarity, though it's a pretty tame R (many PG-13 films out there right now are much worse).