In "Seraphim Falls," a traumatic Civil War incident inspires a former Confederate colonel (Liam Neeson) to ride West for vengeance.

Two mortal enemies share the same nightmare -- and the same epic quest for vengeance -- in "Seraphim Falls."

Part revenge Western, part allegory, this rugged odyssey serves up a gripping tale -- until it wanders into a desert of murky metaphysics at the end of the journey.

Clearly, writer-director David Von Ancken (a TV veteran making his feature debut) and co-writer Abby Everett Jaques don't trust the moral complexity inherent in their basic premise, which has served great filmmakers from John Ford to Clint Eastwood without the kind of mystical mumbo-jumbo "Seraphim Falls" adds to the mix.

But at least they hold off on most of that until the end of the trail.

Initially, "Seraphim Falls" -- the title is the first of the movie's many "Symbol Alert!" clues -- serves up a stark, elemental chase, as the relentless Carver (a driven Liam Neeson) and his hired guns pursue wily Gideon (world-weary but determined Pierce Brosnan) from snow-dusted high country to parched, sandy desert. (The movie is set in Nevada -- it begins in the Ruby Mountains -- but was filmed in New Mexico and Oregon.)

As you can tell by their names, Carver and Gideon are carrying a whole heap o' psychological baggage, but it takes a spell for the movie to spell it out. Seems Gideon is a former Union Army officer trying to outrun his Civil War past -- and Carver's an ex-Confederate out to avenge what Gideon did to wrong him.

We ultimately learn the awful truth. But not before the pursuit leads to encounters with homesteaders, a railroad crew, suspicious missionaries -- and two enigmatic loners.

One, an Indian (Wes Studi) guarding a water hole, dispenses words of wisdom to the parched wanderers ("What you give will be given to you, but what you take will be taken from you") as they slake their thirst.

The other, a snake-oil peddler named Madame Louise Fair (I suppose they could have been more obvious and named her Lucy Fair), played with silver-tongued flair by a disarming Anjelica Huston, materializes to provide temptation and withering witticisms (as when she complains that men always opt for guns instead of remedies).

By then, "Seraphim Falls" has truly plunged over the edge into strained symbolism -- but not before leading us on an otherwise compelling journey.

Borrowing from a variety of sources, including Ambrose Bierce's haunting Civil War and ghost stories, the screenplay presents an intriguing challenge to audiences: Do we root for the hunted or the hunter? And why?

Von Ancken and Oscar-winning cinematographer John Toll use the ever-shifting terrain to reflect our ever-shifting loyalties.

And, at least for some of us, it's so great to see a Western, any kind of Western -- even a sometimes ponderous, sometimes pretentious one -- that we're willing to forgive its trespasses, despite the fact that the central characters aren't willing to forgive each other. Of course, if they were, there wouldn't be any movie in the first place.