This almost entirely-unrelenting film is based on a disturbing true story: that of John Bunting (Henshall), who became one of Australia's most infamous serial killers. He was eventually convicted of 11 murders, along with a cult-like group of followers, psychologically in his thrall, and willing to go along with Bunting's largely homophobic attacks. The movie focuses in particular on the teenage Jamie Vlassakis (Pittaway), who lives with his single mother (Harris) in one of the most dysfunctional areas of Australia, on the northern fringes of Adelaide. Friend of the family Bunting becomes a father figure for Jamie, slowly drawing him into the circle, until the desensitised youth is capable of helping with the murders - usually preceded by torture of the victims - and disposal of the bodies.
It's a glimpse into a corner of hell, with little in the way of redeemable characters or moments to relieve the grimness. As such, it's a bit of a mixed bag: you can't fault the authenticity, with most of the actors not being professionals, outside of Henshall. That separation between him and the other characters, helps give the way he holds them in thrall, a credible air, because he is more obviously playing a role. However, I'd be hard-pushed to claim this gives any particular insight to, for example, the mind of a murderer: Bunting is already a fully-developed psychopath, and there's little or no character development for him, or indeed, anyone else. While I suspect this is probably part of the point, there's virtually no-one here who is at all likeable, and it makes for a bleak, depressing experience. Kudos to Kurzel, assuming that's what he wanted: however, as a viewing experience, this is something to be respected, rather than liked, and contains little that generates any emotions beyond detached distaste.