“The best, and most horrific, film of this year's Toronto film festival...every frame is astonishing.” - 5 star review
“The Act of Killing, by first-time director Joshua Oppenheimer did not disappoint...a film at once wrenching and bizarre: a sequence of colour-drenched tableaus adding up to what must be one of the most complexly fine reckonings with the evil men do – and the stories we tell ourselves, in order to live – as we have.”
"The most unsettling movie about mass killing since 'Shoah'"
"Easily the boldest documentary at Telluride this year - maybe one of the boldest ever seen anywhere - is the Morris-produced 'The Act of Killing'.""A banality-of-evil portrait that culminates in an unforgettable realization of culpability and conscience among the otherwise remorseless killers.""The 'final act of “Killing,” in which one of the gangsters plays one of his own victims on film and is seemingly shattered by the experience, is as vivid an ending as anything you’ll see in fiction or non-fiction this year."
"A documentary like no other I've seen... Hypnotic."
“Werner Herzog said, ‘I have not seen a film as powerful, surreal and frightening in at least a decade.’ I can’t imagine what Herzog could have seen over a decade ago that would trump it.”“We wonder if films can change the world. This one is at least bound to have a devastating impact."
Indonesian review of The Act of Killing in Jurnal Footage
"A surreal, chilling and unprecedented examination of atrocity and accountability, it’s difficult to think of another documentary—or piece of media—that so thoroughly captures a mass murderer’s conscience—as well as charting its evolution."
"The study of the 1965-1966 killings in Indonesia, and for that matter the study of the country’s politics more generally, will never be the same again with the recent release of the documentary film The Act of Killing."- Ariel Heryanto 
"Unforgettable, unmissable, horribly brilliant.”
The Act of Killing is "surreal, disturbing, timeless... Could well change how you view the documentary form..."
"The Act of Killing" is about more than just catharsis for mass murderers. It's about the depth of moral corruption in Indonesia today that enables evil to persist and prevail.” - Daniel Ziv
Canada's Macleans magazine calls "shattering" Act of Killing the best film of Toronto International Film Festival
"Bizarre, hypnotic, audacious, The Act of Killing is also one of the queasiest and most distressing films to play TIFF in the last 15 years."
"A surreal, chilling and unprecedented examination of atrocity and accountability, it’s difficult to think of another documentary—or piece of media—that so thoroughly captures a mass murderer’s conscience—as well as charting its evolution."
Criticwire made a survey among film critics at Toronto International Film Festival: Tom Charity (CNN.com), Steve Dollar (The Wall Street Journal), Jordan Hoffman (ScreenCrush.com), Adam Nayman (The Grid), Jordan Smith (IONCINEMA.com) and Kim Voynar (Movie City News) name The Act of Killing the best documentary at TIFF 2012 (and several other critics call it the second best).