Set in the South during the Civil War, the taut and suspenseful “The Keeping Room” pits three women, living alone on an isolated farm, against seemingly unavoidable destruction. British filmmaker Daniel Barber directs the Gothic Western with elegantly spare style and sinister atmosphere.

“The Keeping Room” is set in the path of Gen. William Tecumseh Sherman’s fiery 1864 march across the South. “War is hell,” Sherman said. Indeed, this film depicts a few days of hell on Earth.

Augusta, her younger sister, Louise, and the slave, Mad, are left behind by the sisters’ gone-to-war father. They have only a few, distant neighbors. There’s a saloon of sorts in the area, too, but not much else.

The area’s isolation makes the small and scattered community easy prey for a pair of marauding Union Army scouts. Supposedly on official military business though they are, Sam Worthington’s Moses and Kyle Soller’s Henry are evil men on an vicious rampage.

Moses’ and Henry’s monstrous acts, both blatant and stealthy, qualify them as monsters in human form in “The Keeping Room.” It’s a film that, but for the absence of the occult, is a horror movie.

Brit Marling plays the resourceful Augusta, a young woman toughened by the deprivation of civilian life in wartime. Augusta can handle a rifle. She and Mad, sensitively played by Muna Otaru (HBO’s “The Wire,” “Syriana”), keep themselves and Augusta’s churlish little sister, Louise, alive.

Hailee Steinfeld (“True Grit,” “Pitch Perfect 2”), one of her generation’s best and busiest actresses, co-stars as Louise. Marling, Otaru and Steinfeld form the trio of fine actresses that the intense “Keeping Room” needs to make its unique scenario work. The rhythm of women’s lives during relatively normal war times, grim though they are, really feels familial.

“The Keeping Room” opens with a violent shock to the moviegoer’s system. A depiction of just how vicious Moses and Henry can be, the scene has no mercy on its characters or the audience. It also is a telling prelude for what’s to come.

Tragically for Augusta, Louise and Mad, Moses and Henry do come to the women’s farm. Some bloody events that follow are predictable, but they still work. Barber skillfully guides screenwriter Julia Hart’s tense stalking scenes, and the women on their own versus men-with-dishonorable intentions is a new take on the familiar home-invasion scenario.

“The Keeping Room” has the making of a below-the-mainstream hit.