The farther up the chain we go, the more we understand that Congo’s image of himself as a hero is not just the delusion of a sociopath, but a fantasy that pervades the highest reaches of Indonesian society. One of The Act of Killing’s most horrifying scenes takes place not at the site of a mass grave but on the set of a talk show in North Sumatra. Congo and his friends are invited on air to discuss their glamorous foray into filmmaking, and then are praised for developing the choking technique that became a “new, more efficient method for exterminating communists.” The peppy female host stresses this line, at which point the audience bursts into applause.

While these powerful men are the closest we get to obvious villains in The Act of Killing, the film doesn’t go out of it’s way to frame them as such. There’s no cut to an interview with a persecuted political opponent to sharpen our reaction to the one with the newspaper publisher. Congo is never confronted by his victims’ families. What’s more, The Act of Killing contains little in the way of historical context. It doesn’t attempt to explain which portion of guilt should go to the Indonesian military that masterminded the killings, or to the Western governments that gave them direct aide to do so, or to the thugs like Congo who did the garroting and stabbing.

The film’s lack of moral handholding makes many people deeply uncomfortable, but this ambiguity is the key to its power. Without a binary of victims and villains, the viewer is unsure whom to root for or against. Indonesians aren’t offered an affirmation or a rebuttal of the façade being presented, and so they can’t fall back on their past assumptions when deciding what to think about the film or its characters. Outside of Indonesia, this moral complexity helps explain why The Act of Killing has managed to shock audiences that, after a century of unfathomable violence, have become inured to the notion of death squad leaders doing horrible things in distant lands. Shock at the killers’ performance of impunity—an emotion expressed by critics and audience members worldwide—is inextricable from shock at the original deed itself. The concept of mass murder is woefully unsurprising to the average news consumer, but seeing it celebrated without any counterbalance from the victims’ perspective presents a messy moral universe, one that audience members themselves must resolve, since the film doesn’t do it for them.

Oppenheimer says his film helps expose the “dramaturgy” of journalism; it says something not only about the storytelling structures through which Congo and his peers process reality, but also those through which journalism processes reality. There is a similarity between journalistic storytelling and Hollywood narratives that present a tidy moral universe of good guys and bad guys, and conflicts that are resolved by the end of the story—a narrative structure that’s as artificial as the façades it pretends to circumvent. It’s become a stock criticism of Oppenheimer’s approach to say that he risked reinforcing the killers’ version of events, but journalistic efforts to get around a façade often end up trapped within the same parameters of debate established by the artifice. A film about the massacre that presented long-suffering victims and unrepentant killers would have played into the same simplistic logic that had already made most Indonesians uninterested in examining the situation.

Oppenheimer understands the appeal of this kind of story. “Within that narrative structure,” he says, “is both a legitimating sense that we are rational and good in contrast to the evil being exposed by the piece, and also the notion that we are hearing something for the first time, reinforcing our own sense of innocence.” The real exposé, he contends, is in showing us things we already know, stories we’ve heard or told ourselves many times, “and forcing us to say, ‘I knew that. Oh, shit. What does it say about me that I knew that?’ ”

While it’s far from a Hollywood ending, Congo’s participation in the film brought him to a similar self-realization. In the film’s final scene, Congo is shown on a rooftop where he performed many of his executions. He launches into yet another self-justification to the camera, but then stops short and begins to gag. He tries to compose himself, then gags again, a frightening mirroring of the victims he strangled in this very place.

Michael Meyer is a CJR staff writer. Follow him on Twitter at @mcm_nm.