From the delicious pleasures of a well-turned card trick to the obfuscations of media snake-oil salesmen, Robert Kenner’s documentary explores how big businesses have used sleight-of-hand to distract public attention from scientific fact in the battle for climate-change consensus. Building upon lessons learned by the tobacco industry, those free-marketeers with a vested interest in resisting emissions legislation (or, indeed, legislation in general) have conjured “doubt” from thin air in a concerted campaign of poisonous public prestidigitation. Unravelling the myriad methods through which ideology consistently trumps evidence (we see what we believe, not vice versa), Kenner flits between the enclaves of the Magic Castle in Los Angeles and the newsrooms of the world’s media, explaining how carnival-huckster showmanship has been used to make hard-and-fast scientific evidence of man-made global warming disappear before our very eyes. Hey presto indeed.