Three years ago, viewers flocked to a brazenly non-ironic re-make of Tobe Hooper's 1974 cannibal classic.

In the prequel we watch a man being tortured and - as the clock ticks - director Jonathan Liebesman all but sprays the screen with cartilage. Not so much scream as squirm.

The meat of the film is how - back in 1969 - Thomas "Leatherface" Hewitt got his name. Attacked with equal gusto is the question of how Tom's uncle Hoyt (R Lee Ermey) - aka the town sheriff - lost his teeth. Here, as an ex-GI constantly invoking Korea, the brilliant actor is chilling.

The film throws two sexy brothers (and their girlfriends) in his path. One of the youths is returning to fight in Vietnam, the other, in defiance of his dad's wishes, is about to dodge the draft. Hoyt's position is clear: the family that slays together stays together.

Without doubt, this is a cruder work - dumber, nastier - than the Hooper original. But, via the war-dancing Hoyt, it's got something very right. Does the film's institutionalised, white-trash sadist represent the dark side of the military or the norm?

Whatever your views, connections between the slaughters on screen and real-life horrors are hard to avoid. The Iraq conflict overshadows every frame of this Beginning. The one comfort: in the cinema, at least, there's an end in sight.