But fiction comes with a warning, specifically that it is fiction. You can fact check non-fiction but fiction is completely open about the fact that you should consider what it's saying to be suspect - the default position on it is "this is made up".

The danger is - and Argo is one example but there are far, far worse (cough Dan Brown cough) - where you get fiction "based on true events". There are some lovely fictional biopics based on real people (Carter Beats the Devil springs to mind) but when you get the likes of the Da Vinci Code being taken as having some underlying truth I can see where you're coming from.

But I doubt very much that those people believing the "truth" in those works of fiction are the people fact checking non-fiction. In both those cases it feels as if the book isn't the problem, the person is.