Going head to head with one of the greatest horror films of all time is bound to end in bad blood, but while this reimagined 'The Texas Chainsaw Massacre' is no real match for the original, it has just enough mad mayhem and hysterical helter-skelter to satisfy most horror-fiends – and a film about a terrifying family of mad Texans wielding ruthlessly lethal power from a big white house has never seemed more pointedly political.