In short, this is a book documenting the CIA's activity within the Congress for Cultural Freedom, an organisation set up to combat growing communism in Western Europe and America after the Second World War. Saunders is meticulous in writing down every (known) dollar that went in and out of the committee, and every event set up, too.
He makes a strong case that most post-war culture in Europe and America has been influenced by American foreign policy.
Perhaps I'm not enough of a hardcore conspiracy theorist, but I did find it hard to keep interest in a narrative that picks up every small detail about every single dollar that gets passed around by the CIA.