There's a wealth of valuable and urgent info in Robert Kenner's study of how business and ideological interests... create the illusions of debate and doubt over such issues as climate change in the media arena when none ought to exist.

It's nice to see the problem of climate change tackled from a new angle, but this is still another form of preaching, another film designed to outrage. But how is the audience meant to channel that outrage?

Using a magician's tricks as a metaphor for corporate tactics is clever, and Kenner's found an eloquent talking head in history of science prof Naomi Oreskes, but as in his previous flick, Food, Inc., he keeps hammering away at the same idea.