At Venice, Telluride, Toronto, and the New York Film Festival half a year before Human Rights Watch Film Festival and commercial release, The Look of Silence is a reminder of what the world chooses not to know.

At any given moment there are some three dozen wars and/or holocausts, most not sexy enough to blip global radar. One glaring example, half-to two-and-a-half million dead, is Indonesia’s agony following an abortive 1965 junior officers’ uprising which led to in effect a military coup and purge of “communists.” In this new film and in his multi-prize-winner The Act of Killing (MoMA-Lincoln Center 2013 New Directors/New Films), Joshua Oppenheimer documents the nearly unknown events and aftermath echoing up to the present. The earlier work concentrated on the largely civilian killers who remain respected rewarded heroes of the régime, whereas, now, the handful of survivors and the relatives of those many murdered and disappeared emerge from their cowed half-century silence which like a cancer grows.

Crew and participants running risks -- Indonesians are credited as “Anonymous” -- the ninety-nine minutes rubs the world’s nose in the horror of North Sumatra, one of four hardest-hit provinces, where the dirt poor must survive alongside -- or rather under -- their empowered civilian neighbors who, recruited by the army, had imprisoned, trucked away, tortured, butchered and mass-buried their loved ones. These underling criminals even include their own family members, for example Ramli’s well-to-do maternal uncle, who denies knowledge and then personal responsibility before waxing indignant.

Hauled away and hacked, Ramli had escaped and, trailing blood, crawled home to his parents’, only to be tracked and returned, not to a promised hospital, but to the Snake River killing grounds, where his penis was sliced off before he was killed. Unique among hundreds of thousands, this death was witnessed and therefore public knowledge.

The young man’s mother Rohani and nearly vegetative father Rukun -- a mischievous sixteen years old by his own count, a hundred forty by his wife’s -- are major sympathetic figures. Dignified in front of Lars Skree’s uncomfortably all-revelatory lenses, they cope in helplessness and the silence which the film would break. The act of declaring faces the past in a manner not at all like the Reconciliation of South Africa, for, despite cosmetic changes in Indonesia, the evildoers still reign supreme.

Now forty-five, Adi was, among his siblings, Rohani’s replacement for the older brother martyred three years before his birth. An optician without an office, he is occupationally able to one-on-one with everyone, including the perpetrators, some of whom recall the film director from the earlier documentary.

None of them is repentant. The past, they say, cannot be fixed, anyway, but some become belligerent and all are self-righteous about their deadly services to the nation. No wonder, because to this day propaganda pictures the dead as irreligious undesirables, cruel, wife-swapping communists whose very progeny are cursed, prompting Adi to bridle at the schoolroom indoctrination hammered at his two children.

Two of the interviewed proud hero-murderers particularly catch the attention. Comic if this were not atrocious horror, they are upset at not having brought along a machete for their reenactment -- Rohani and Ramli’s bicycle ride is, in contrast, film or dream reenactment, one of the few non-direct cinema interventions and a questionable one. As the two preen for the camera through what otherwise would be a laughable routine, the shock sets in that these bumblers are in fact Rahmi’s very assassins, untouched and untouchable. They happily show off and it is made even more chilling by the later presence of the one villager who escaped that fateful night and accompanies Oppenheimer back to the site and then to Rahmi’s folks’ house.

Ten thousand comfortable miles away, one is sickened. Mercifully, one cannot imagine what must be going through Adi’s mind as he faces his brother’s killers in the fragile ageing flesh or watches selections from the first film.

(Released by Drafthouse Films and rated "PG-13" for thematic material inclucing disturbing graphic descriptions of atrocities and inhumanity.)