“A boy is a dangerous thing,” says the Commandant.

Fresh from directing True Detective, Cary Fukunaga delivers another cinematic masterpiece this year: Beasts of No Nation. Starring Idris Elba and newcomer Abraham Attah, the movie follows the life of a young boy torn from his family by war. It shows the slow, insidious transformation of a child into a murderer.

When the movie begins, the audience is introduced to Agu, a playful boy from a good family in Western Africa. His father is a teacher, and his mother, a God-fearing Christian. They go to Church every Sunday, along with his girl-crazed older brother and baby sister. For a while, Agu is happy.

But good things do not last. With war approaching, his mother and sister flee the village. Trapped in a war that he did not ask for, Agu is helpless as the national army crashes through his town. He watches, shaking, as his father and brother are shot down mere feet from where he stands. He sees things that no child should see. By some miracle he escapes the gunfire that took his family. Perhaps the national army did not consider the small, preadolescent boy a threat. They could not have been more wrong.

Starving and weak, he is discovered by the Commandant (Idris Elba), the leader of an unnamed rebel group fighting in the civil war. Cunningly charismatic and ruthlessly calculative, the Commandant sees in Agu what he does not see in himself: a weapon. Agu is thrown in a group with other child soldiers who are already initiated. They smoke together, rap with each other, and support each other. It is almost hard to remember that they are killers.

The first time Agu kills a man is a gruesome scene. The Commandant considered the killing a right of passage, the final step in the boy’s transformation. The man was bound, staring at the boy with tear-filled eyes as he begged “Please, please…” Agu hesitated, and the Commandant encouraged him: “These are the men that killed your family, Agu. These are the men that killed your father.” And in that instant it was no longer a boy who stared back at the man; it was a beast. Transformed by pain and molded by suffering, Agu had become numb.

He hacked the man to pieces with a dull machete.

From that point on, the audience rarely saw the playful, happy boy who came from a good family. No, instead they saw the weapon. They no longer saw the child but rather the killer. Agu was no longer innocent. He was no longer a child.

From that point on, Agu only becomes more hardened, more eager to please his Commandant. “I am a good follower, sir,” he would say again and again. Early on he tries to stop killing, but notes that if he does not kill, the Commandant will kill him.

Agu regards the Commandant with the awe and reverence of a son to a father. To him the Commandant is larger than life, his savior, teacher, and leader all rolled into one. One of the most powerful scenes in the movie is when the Commandant, drunk and intoxicated, complains unreservedly with unwilling resignation about the choices of his superior: the Supreme Commandant. The audience sees a shift in Agu’s world. The Commandant, this once all-powerful entity, had those who he had to answer to as well. Agu realizes that the Commandant is merely a pawn in the larger effort of the war, disposable and replaceable. In fact, the latter half of the film revolves around the Commandant’s fall from grace. His refusal to relieve his power causes a second civil war within the first. Elba brilliantly portrays the Commandant’s descent into desperation, ranging first from aggressive ambition to the pleading characteristic of the powerless.

Agu’s battalion, starved, diseased, and out of ammo, abandon the Commandant and surrender to a United Nations armed force patrol.

Agu and the other children are placed in a rehabilitation center for child soldiers traumatized by the war. Counselors try to convince Agu to open up about his experiences. He regards them with contempt. He does not open up. How could they understand when they have not taken a life? How could they understand that in taking a life his childhood was taken away from him? He was forced to grow up, deaden his conscience to survive. So no, he does not open up. He only tells them that he used to be a good boy, that he came from a good family.

The film ends with Agu saying wistfully that he just wants a happy life. “I cannot go back to doing child things,” he reflects mournfully.

The film ends optimistically, suggesting that with time Agu could heal. This is often not the case. The great majority of child soldiers die, and the ones that survive can never return to normal lives. War kills many people, but it is often the ones who survive that suffer the most.

Gripping until the end, Beasts of No Nation grabs the audience’s attention and forces them to look at atrocities better read about in picture-less articles. That being said, Fukunaga masterfully balances the amount of violence in his work. What is not directly shown is done implicitly, and often produces an effect of the same magnitude. Fukunaga impressively captures the horror of child soldiers without any added dramatic effect. The tone of the movie is objective, and any savagery is revealed through that neutral lens. True horror does not need any dramatization to be understood.

The film is available for streaming on Netflix and viewing in select theaters.