| Director | S. Craig Zahler, Steven Craig Zahler |
|---|---|
| Genre | Western film, horror film |
| Runtime | 132 min |
| Country | United States |
| Budget | $1.8 million |
| Box office | $475,846 |
In the 1890s, brigands Purvis and Buddy encounter a Native American burial site. They are ambushed, and Buddy is killed while Purvis escapes. Purvis reaches a nearby town, Bright Hope, and buries his loot. Seeing this, backup Deputy Chicory reports him to Sheriff Franklin Hunt, who interrogates Purvis. When Purvis attempts to flee, Hunt shoots him in the leg.
Hunt sends the confident gunslinger John Brooder to fetch the town's doctor to tend to the leg wound. However, he fetches Samantha O'Dwyer, the doctor's assistant, who is caring for her husband Arthur, who has an injured leg. Hunt leaves Samantha in his office with his other deputy, Nick, to tend to Purvis' wounds.
That night, a nearby stable boy is killed. Hunt learns of the murder and goes to his office, finding it empty, with an arrow left behind. The Professor, an educated Native American, links the arrow to a tribe of troglodytes and locates the valley they inhabit on a map. He warns Hunt that they are a group of inbred cannibals, shunned and avoided by other native tribes. Certain that Samantha, Nick, and Purvis have been captured by them, Hunt forms a rescue party with Chicory and Brooder. Arthur insists on accompanying them to find his wife, despite his injury.
Days into their ride, two strangers stumble across the rescue party's camp. They are killed by Brooder, who fears they are scouts for a raid. The rescue party set up a new camp, but they are ambushed by raiders who injure Brooder's horse and steal the rest. The following day, a fight occurs between Brooder and Arthur, exacerbating Arthur's leg wound. Chicory leaves him to recover while he, Hunt, and Brooder continue on foot. Reaching the valley, the rescue party are ambushed by the troglodytes. The rescuers kill three, but Brooder is killed while Hunt and Chicory are captured.
Hunt and Chicory are imprisoned near Samantha and Nick. She explains the troglodytes have already killed and eaten Purvis. The group witnesses Nick stripped, brutally scalped, bisected alive, and then consumed. Hunt tricks several troglodytes into drinking from his liquor flask which has been laced with opium tincture. The troglodytes throw the flask into a campfire; one dies while another becomes unconscious. Samantha estimates there are seven remaining male troglodytes.
Arthur follows his rescue party's trail into the valley. He kills two troglodytes and discovers they use an animal bone in their windpipes as a whistle. He blows on it, luring another troglodyte, then kills him.
In the cave, the troglodyte leader grows angry at the poisoning. The troglodytes cut open Hunt's abdomen, shove the now heated opium flask into the wound, and shoot him. Arthur arrives and aids Hunt in killing the leader. He frees Samantha and Chicory. A mortally wounded Hunt stays behind with a rifle, promising to kill the remaining three troglodyte males when they return, to prevent them from terrorizing Bright Hope. As the three leave the cave, they see two pregnant troglodyte women, who have had all their limbs amputated and stakes driven into their eyes to blind them. After the party is at a distance from the valley, Arthur blows on the troglodyte whistle, with no response. Later, they hear three gunshots in the distance.