Viewers of The Thick of It will know of special advisers as spin doctors and political careerists. Several well-known ministers have been special advisers, among them David Cameron, Ed Miliband, Jack Straw and Vince Cable. People also know about the public relations disasters involving Jo Moore, Damian McBride and Adam Smith. But what is the reality? What do special advisers actually do in government? Who are they, where do they come from, and...