“I have done that,” says my memory. “I cannot have done that,” says my pride, and remains inexorable. Eventually—memory yields.

–Friedrich Nietzsche, Beyond Good and Evil

“The Act of Killing” proves Nietzsche was too optimistic. This surreal documentary, which feels more like Variety Hour in Hell, began when filmmaker Joshua Oppenheimer found that it was impossible to get survivors of the brutal 1965-6 anti-Communist campaign in Indonesia to describe their experiences. He settled for what he considered the next best thing: interviews with the perpetrators. And for the reason Jean-Luc Godard gives here, that turned out to be the key to making one of the most eye-opening documentaries I’ve ever seen.

Because the killers were so proud! They boasted–and they didn’t just boast about killing Commies. They boasted about lying, labeling everybody Communist in order to have an excuse to kill them; they boasted about corruption and bare-faced bribery. They boasted about the grubbiest little crimes as well as the atrocities. They call themselves premen, a term which the film translates as “gangster” but which–as they frequently point out–is derived from the English “free man.” It covers everybody from the man who scalps tickets outside the movie theater to the man who slaughters ethnic Chinese.

Oppenheimer asked these men to reenact their killings in whatever way they wished. At first the reenactments are fairly straightforward: This is how I would loop the wire around the guy’s neck, this is where I did it. Then, as Oppenheimer would play their reenactments back for them and ask how they wanted to do it over, the scenes start getting seriously wiggy. There are Western-themed reenactments and noir-themed ones, and a glorious dance scene in front of a waterfall in which a victim thanks his killer for sending him to Heaven. There are interrogation scenes in which the interrogators still have “victim” and “pretty lady” makeup on from previous scenes. It’s a vertiginous experience which makes a lot of points–for example, the gangsters are very up-front about the fact that they are consciously modeling themselves and their techniques after what they saw in movies, the way American mobsters adopted the style of The Godfather–and makes the audience feel like reality itself is up for grabs.

The premen created an identity in which violence, lies, and self-seeking were praiseworthy. “Relax and Rolex!”, as one of them chortles. They use “sadistic” as a neutral-to-positive term. I wondered whether not only fear but also the lack of any corresponding positive identity as a survivor explained the reluctance of their victims to go on the record. The killers are often explicit about their desire to create an internal reality in which their actions were admirable: They work hard to make themselves the heroes, not the villains.

And they’re comedy heroes. There’s a lot of laughter in this movie, usually after knee-slappers like, “Now that I’m governor, I can stab him if he threatens me!” The bad guys won, and that makes them the good guys now.

But “Act of Killing” suggests that conscience isn’t always as malleable as we might like. I don’t intend to trivialize the torture and murder committed by Oppenheimer’s stars when I say that I think everybody can relate to the experience of feeling our definitions of morality, guilt, and unconscionable behavior stretch and shift so that our own sins become bearable. Conscience is elastic. Some of the men portrayed here seem to have successfully suppressed any sense of wrongdoing, and in fact view themselves as victims of a foreign human-rights establishment. But others are clearly haunted. Anwar Congo, one of the most fascinating of the premen, admits that he has nightmares and that he used to seek release in drugs, alcohol, and dancing. Another asks, “If my dad were a Communist and you killed him, I’d be upset with you. Is that normal?” (A more confident killer suggests that he should seek psychiatric help, to cure his conscience.) Reenacting his crimes brings him to a painful realization of the humanity of his victims.

This is a movie about how language creates and limits conscience–there’s a great, bizarre little snippet of debate about the difference between “cruelty” and “sadism”–about how, as one man says, “From one perspective, it’s not wrong. That’s the perspective you have to make yourself believe.” There are sentences which can’t be finished: “I’m not calling you a liar, but logically….”

And there are some scenes which are just glorious filmmaking. The transition from Congo, exhaling cigarette smoke on the set of one of his final reenactments, to Congo slowly rising on the mechanical camera apparatus, is noir genius in the Citizen Kane style. The sublimely disorienting, shocking waterfall scene is grotesque and heartbreaking.

Since the movie came out, Indonesian media have begun printing similarly brazen interviews with the 1965-6 killers. The movie snuck in under the censorship radar and, by letting the premen present their pasts in their own words and images, may have given them enough film to–figuratively, only figuratively–hang themselves. Whatever happens as a result of this movie, though, it’s a must-see: philosophically rich, visually stunning, emotionally devastating.