THE SWEET HERE- AFTER, by Russell Banks, Harper Collins, 257 pages, $20.

An odd phenomenon strikes those who sit through trials, who listen to day after day of testimony: even if the central facts of the case are known from the start, reality has a way of continually remaking itself in the courtroom. Old stories are retold with new shadings, and new details emerge where they are least suspected.

“The Sweet Hereafter” contains no courtroom trial, but Russell Banks has constructed his story so that four witnesses give their testimony directly to the reader. Immaculately crafted, these characters send readers out onto the shifting plain of truth, where, pitching forward, they never quite catch their balance.

The central fact in this novel is a school bus wreck, a villainless crime that claims the whole town of Sam Dent, N.Y., as its victim.

Delores Driscoll, the unscathed bus driver, opens the book with her prattling version of the morning of the accident, up to the moment the bus plunges over the embankment. Town hero and secret drunk Billy Ansel, who has lost his whole family by the time we meet him, then repaints the accident scene, and covers the hours and days that follow.

Mitchell Stevens, a personal injury lawyer from New York, recounts those first few days and the weeks that follow. Nichole Burnell, the eighth-grade beauty crippled and disfigured in the accident, then gives her pitiless version of the rest of that year. Delores reappears at the end to narrate her re-emergence into public life, at the town fair’s demolition derby.

Banks, a New Hampshire native, has shifted his venue a little closer to his current, upstate New York home in “The Sweet Hereafter.” But his Sam Dent could be any rural New England town; like all of Banks’ settings, it is an uncannily honest rendering of rural places and people.

His great achievements in this book are his characters, who sizzle with understated passion. Banks’ details etch these people onto the reader’s mind; in their own masterfully captured voices, they betray their quirks and scars, and the shared pathology of the community.

“It’s a way of living with a tragedy, I guess, to claim after it happens that you saw it coming, as if somehow you had already made the necessary adjustments beforehand,” Billy Ansel observes in his narration. “I could understand that. But it still irritated me to hear it.”

The bus accident is the perfect trigger for the subtle, radical shakedown of this town. It offers no easy answers, and no escape from the pain. And, for the reader, the wreck is all too believable.

“The Sweet Hereafter” is smaller in scope than Banks’ last two novels, “Continental Drift” and “Affliction.” Where those spanned generations, combining the epic with touches of the mystic, “The Sweet Hereafter” is a straightforward tale surrounding a single event.

The approach allows Banks to focus his powers of description, his penetrating eye and ear. The result is a novel that is Banks’ best effort yet, a complete and unwavering story.

Over the last six years, critics have hailed Banks as one of America’s great developing novelists. With “The Sweet Hereafter,” Banks announces that he has mastered his craft.