Anwar Congo in Joshua Oppenheimer’s film “The Act of Killing.” Image by Drafthouse Films / Everett

On the evening of September 30th, hundreds of men from the Islamic Defenders Front, an Indonesian hard-line Muslim group, streamed into a large square in east Jakarta. They had come to commemorate the fiftieth anniversary of the murder of six anti-Communist Indonesian generals by left-wing conspirators, including members of the Indonesian Communist Party (Partai Komunis Indonesia or P.K.I.). Fifty years ago, Suharto, one of the few surviving major generals, responded by assuming control of the military and routing the poorly organized left-wing plotters. He portrayed their plot as an attempted coup and used it as a justification for rounding up and murdering hundreds of thousands of alleged Communists throughout Indonesia. Today, Indonesia’s state officials continue to support the Suharto line: that the generals’ murders represented a full-blown coup attempt and that the 1965 killings prevented an otherwise imminent Communist takeover. Fifty years after the event that set the mass murder in motion, the men in the courtyard had come to watch a film about the slaughter.

There were a few speeches before the film began. The Jakarta police chief, Inspector General Tito Karnavian, denounced Communism and paid homage to the slain generals. “Islam and Communism cannot exist together,” Karnavian said, arguing that Indonesians should remain vigilant against any ideology that threatens Islam. Habib Rizieq, the fiery head of the Islamic Defenders Front, also denounced the long-defunct P.K.I. Rizieq said that his family had been among those that were threatened by the P.K.I. He denounced attempts to rehabilitate the Party, which he said would only lead to Communism's reëmergence. “The police and military must watch out to insure that the P.K.I. doesn’t rise again!” he said.

Finally, Rizieq pivoted to his major point. “Why don’t we know our own history?” he asked. “Because after Reformasi”_—_the transition to democracy that followed Suharto’s reign—“we were too afraid to show ‘Pengkhianatan G30s/PKI.’ ”

Until 1984, Suharto’s regime did not release any films that directly addressed the events of 1965. The best explanation for this, according to Krishna Sen, the dean of Indonesian Studies at the University of Western Australia, is that Indonesia’s wounds were simply too raw. She recounted a conversation she had with Rear Marshal Budiardjo, Suharto’s minister of information from 1968 to 1973, about the government’s decision not to release a 1968 film that a Suharto loyalist had made about the Army’s triumph over the P.K.I. “Why would we advertise a civil war?” he said to her.

But in 1984 Suharto’s New Order regime, which was beginning to face popular resistance, changed tack. The government funded a major film production about the killings, guided by the accomplished Indonesian director Arifin C. Noer, with the working title “A History of the New Order.” The resulting film, the docudrama “Pengkhianatan G30s/PKI_”_ (“Treachery of the September 30th Movement/PKI”), is in part a “Reefer Madness”-style horror flick depicting gruesome Communist atrocities, many of which never occurred. In perhaps the film’s most famous scene, three of the captured anti-Communist generals are brutally tortured—their eyes are gouged out, lighted cigarettes are put out on their skin, they are repeatedly whipped and stabbed—while Communist women perform a macabre dance ritual to celebrate their death. (In fact, according to one of Suharto’s surviving medical examiners, who inspected the generals’ bodies, there were no signs that they had been tortured before they were shot.) Even more telling than the film’s exaggerations are its elisions: it concludes with the recovery of the slain generals’ bodies, and shows a dashing Suharto defeating Communists and restoring order to the country, but does not depict the military’s extermination of hundreds of thousands of alleged P.K.I. supporters.

The Suharto regime considered the film such an effective exercise in propaganda that it mandated annual showings in schools and on TVRI, the state television channel, from shortly after the film’s release, in 1984, until the regime’s collapse, in 1998. A poll conducted in 2000 by Tempo, Indonesia’s investigative weekly, found that ninety-seven per cent of Indonesian secondary-school students had seen the film at least once, with eighty-seven per cent of those who had watched the film reporting that they had seen it multiple times.

Given the rising disaffection with Suharto’s regime during those years, it might not have been as effective a propaganda tool as he had intended. “I don’t know if propaganda succeeds in a situation where people are already disenchanted,” Sen said. Still, the graphic violence of the film shocked Indonesian students into believing that Communists were evil. Dian Agustino, a thirty-four-year-old communications consultant, vividly remembers a reënactment of the murder of Adi Irma, the daughter of an anti-Communist general. “We were so sympathetic to her because she was just a small child, who was killed even though she hadn’t sinned,” Agustino said. The film found its way into childhood games and rivalries, she added. “The most awful kid at school, we’d refer to as P.K.I., or if I was mean to you, you’d call me P.K.I.,” she said.

In 1998, the Asian financial crisis sent the value of the Indonesia rupiah plunging. Sky-high inflation, combined with revelations about the corruption of Suharto’s inner circle, caused large protests throughout the country. Finally, the military withdrew its backing of Suharto, whose thirty-two-year rule came to an end. Reformasi followed, ushering in Indonesia’s democratic system. Bans on the press were lifted, and magazines that had been shuttered by Suharto quickly returned. September 30th, 1998, marked the first anniversary of the generals’ killings that “G30s/PKI_”__ _was not broadcast on TVRI, or widely shown in schools.

The liberalization of media meant that Indonesians could, for the first time, openly discuss different accounts of the events of 1965. Angelina Anggraeni, a thirty-three-year-old architect, who grew up learning Indonesian history from the film “G30s/PKI”_ _as well as from Suharto’s textbooks, finally began reading deeply about the killings. “After 1998, I realized, Oh, that was all brainwashing,” Anggraeni said.

It was not until 2012 that another prominent Indonesian-language film dealt directly with the 1965 killings. It came from an unlikely source. Joshua Oppenheimer, an American filmmaker, had been sent to Indonesia by an international union in the early 2000s to give filmmaking tutorials to plantation workers in North Sumatra. The workers, many of whom were dying from diseases caused by exposure to pesticides, wanted to make a film about their efforts to form a union. But the Belgian company that owned the plantation hired a local paramilitary group, the Pancasila Youth, to terrorize the workers, and they gave up on the union. Some of them explained to Oppenheimer that the Pancasila Youth had killed their parents and grandparents for being a part of a union, in 1965. “It wasn’t just the poison that was killing the workers, it was fear,” Oppenheimer remembers thinking.

In 2003, Oppenheimer began interviewing survivors of the 1965 killings, but the Army got word and compelled survivors to stop participating. Still, the survivors implored Oppenheimer to make the film regardless, and they offered him an odd suggestion: perhaps he could speak with the perpetrators, who were often vocal about their involvement. And so members of the Pancasila Youth became the protagonists of Oppenheimer’s first film about the slaughter, “The Act of Killing,”_ _in which Oppenheimer shows members of North Sumatra’s Pancasila Youth making a film about slaughtering leftists in 1965. On-screen, Paramilitary members brag about the murders they perpetrated, but also, at different moments, make blunt admissions about the guilt that haunts them. Oppenheimer’s next film, “The Look of Silence,” switches focus by exploring the way that violence has affected the relatives of the victims. The film follows Adi, a middle-aged optometrist, as he seeks the true story about his older brother’s murder by anti-Communist paramilitaries. The juxtaposition of Adi’s family’s fear and grief with ex-paramilitary members’ cheerful memories of torturing his brother and dumping the corpse into a river captures both the horror of the 1965 mass murder and the ways in which modern Indonesia has so far failed to reckon with it.