What begins as a deliciously ripe allegorical tale that plays on a fundamental mistrust of outsiders, ever heightening class and inter-class tensions, and America's obsession with constitutional rights, rapidly descends into an ugly mess of plot collapses and lapses of sense. This is a huge shame as the central premise within The Purge, as audacious as it might be in its 70s B-movie conceptual pretensions, has a great set of razor-sharp satirical teeth. In 2022, crime and unemployment is at an all-time low. The economy flourishes, and things are about as utopian as they get. This is, we are told, due to an annual 12-hour "purge", a government-sanctioned half-day of lawlessness where anything and everything goes - penalty free. On news magazine shows, talking heads discuss how man's innate savagery is tempered by allowing this periodic cathartic release of ultra-violence to stand. In the hours leading up to the event - imagine the Queen's Jubilee but with semi-automatics - news anchors fervently discuss the cleansing nature of the purge, and the Sandin's neighbours openly angle-grind homemade machetes. Had the film been more about the terrifying fanatical way credence is leant to the purge as a quasi-religious day of spiritual absolution or the Republican dream of allowing society's weakest and poorest to be Darwinially expunged from their streets, and less about James Sandin (Hawke) and his one-dimensional family of morons, this would have been a corker of an entry into the tired home-invasion canon.