The title of Alejandro Landes’ film is the name given to a squadron of young guerilla fighters stationed atop a towering mountain in an unnamed South American country (it was shot in Colombia). One translation could be “The Monkeys,” but the eight are not to be confused with the old rock group: these are feral, ferocious child soldiers, driven less by dedication to any ideology than by sheer animal instinct.

There’s a natural inclination to frame a story like “Monos” in terms of classic tales about the reversion to savagery—the “Lord of the Flies” template, to which there’s actually a visual allusion at one point. But the members of this team don’t descend into a primitive state; they simply inhabit it from the very start, and the screenplay offers no backstory to suggest that they were ever civilized in any conventional sense. They simply are what they are, a bunch of toughs answering to their assigned names: Wolf Julian Giraldo), Dog (Paul Cubides), Bigfoot (Moisés Arias), Swede (Laura Castrillón), Boom Boom (Esneider Castro), Lady (Karen Quintero), Smurf (Deiby Rueda) and Rambo (Sofia Buenaventura).

In between visits from their commander Mensajero (Wilson Salazar), a diminutive fellow who makes up for his lack of height by barking out orders and insults with the gusto of R. Lee Ermey in “Full Metal Jacket,” the members of the squad go wild with drugs and drink, constantly baiting one another and pushing their fellow comrades around like members of a football team at practice. It’s a school of hard and harder knocks.

There are duties to be seen to, however. One involves taking care of a recent arrival—a cow called Shakira that has been temporarily donated to the movement by a supporter as a source of nutritious milk. But it will have to be kept in prime condition, since it will eventually have to be returned to its owner. A second centers on another newcomer—a female engineer (Julianne Nicholson) who has been taken captive and is being held for ransom. She has to be kept in a saleable state.

But given their lack of discipline when Mensajero is away—which is most of the time—they fail at their responsibilities, first with respect to Shakira, which winds up dead, graphically slaughtered and eaten, and then in terms of the hostage, who escapes after a government raid on the camp is repulsed, and has to be recaptured. The group attempts to devise an explanation that might satisfy Mensajero, but it involves a deception that eventually falls apart and threatens whatever is left of their feelings of solidarity with their supposed cause.

As the survivors repair into the dense jungle, they descend into fighting one another as well as the discipline of Mensajero, along with anyone else that gets into their way—including a family that takes Rambo in after she attempts to steal their boat. The ending leaves the fate of many of the characters inconclusive or ambiguous.

“Monos” is visually quite remarkable, with Jasper Wolf’s images of the remarkable locations frequently stunning—and menacing—and Mica Levi’s score helping to keep one on edge. As written none of the roles call for much subtlety, and the performances are more strident than nuanced.

But that’s of a piece with a film that takes you to a visually arresting place but surrounds you with people you’d never want to meet. “Monos” is raw and uncomfortable to watch, but it undeniably leaves a lasting impression.