This enthralling film, based on the book by Naomi Oreskes and Erik M. Conway, is as fascinating as it is horrifying.

An issues documentary that scores its points through a seductive combination of clearly stated arguments and pithy humor.

An intelligent, solidly argued and almost too-polished takedown of America’s spin factory — that network of professional fabricators, obfuscators and pseudo-scientists who have lately attempted to muddle the scientific debate around global warming — this is a movie so intrigued by its designated villains that it almost conveys a perverse form of admiration, and the fascination proves contagious.

Merchants of Doubt has its moments when the professional deniars hem and haw about who pays them to do what they do. But mostly, they’re glib, smug, self-confessed and self-righteous tools of Big Coal, Big Chemical or Big Oil.

As they’re akin to spectators at a magic show, viewers ought to keep an eye out for what the Merchants of Doubt don’t want us to see.