All kinds of lines — those separating good and bad, past and present, and even international borders — are blurred in this neo-Western gem. Though it’s entirely set in a small Texas border town, Lone Star pulls off all the gravity and sweep of an epic thanks to its seemingly-micro-actually-macro focuses and sprawling ensemble. It’s all kickstarted by the discovery of a skull in the scrub near Frontera, Texas; Sheriff Sam Deeds (a quietly captivating Chris Cooper) thinks he knows who it belongs to and who might have buried it there: his deceased father Buddy (Matthew McConaughey), the much-loved former sheriff of the town whose shadow Sam has long been living in.

And so an investigation of this historic crime begins, unearthing along the way many more skeletons — both individual and national — as Sam interviews those who knew his father and the victim. Lone Star’s brilliance is in the way it entwines with Sam’s investigation a broader exploration of America’s sins and their lingering legacies, particularly the many-headed effects of its history of racism. Lone Star weaves its political and personal elements together with seamless flourish, making for a rich tapestry of America’s past and present that never sidesteps the grander questions it provokes.

The editing (by writer-director John Sayles) is certainly a highlight — flitting between the past and present with both visual and narrative smoothness — but we’d be remiss not to spotlight the superlative ensemble here. From Sam’s childhood sweetheart Pilar (Elizabeth Peña) and her haughty mother Mercedes (Miriam Colon) to the commander of a local army post (Joe Morton) and his estranged father Otis (Ron Canada), Lone Star boasts a true-to-life tangle of characters who give the film a deep sense of being lived in. Add to that some magnetic bit-parts — including Beatrice Winde as a sharp-tongued, Game Boy-loving widow and Frances McDormand as Sam’s overwrought ex-wife — and Lone Star becomes a banquet of unforgettable performances.