Umberto Eco's latest novel, "The Prague Cemetery," has received tons of attention. But few reviewers have added anything interesting in their criticism, other than the usual banal stuff (not necessarily untrue) of it being "boring" or "over-stuffed" or intellectually ambitious, but less successfully executed. If you want something interesting, check out Neal Ascherson's take in The New York Review of Books. He actually has plenty of nice things to say, but the most novel critique comes at the end.
Ascherson argues that Eco may have many things right about the nature of conspiracy theories, from the way they're seized upon by the recently powerless and marginalized, to how they're manipulated by the powers that be. But when it comes to Jewish conspiracy theories, upon which Eco's novel is based ("The Protocols of the Elders of Zion," the 19th century Russian forgery which imagined a Jewish plot to take over the world), the author missed an opportunity. Jewish conspiracy theories like "The Protocols" aren't a modern phenomenon, as Eco suggests. They're as ancient as Judaism itself.
The pagan Romans, Ascherson points out, even had their own anti-Semitic conspiracy theory about Jewish world domination. They said that the cult of Jesus Christ was nothing but a group of Jewish schemers who planned to dominate the world. Problem was, they were right.