The Lost Symbol by Dan Brown.
He's an author who became famous for the controversy surrounding the story in Da Vinci Code rather than any actual quality of his writing, and I will give him credit for Da Vinci Code and Angels and Demons both being perfectly passable thrillers. But his other two books that had come out at that time, Deception Point and Digital Fortress, showed how shallow his skill set is, because you can pretty much guess both the twists and the main villain's identity from the first couple of chapters. But with the Lost Symbol things just became absurd. The writing is awful, and there was no credibility to the plot line at all. It was basically Robert Langdon (who, for those who don't know, is also the main character from Da Vinci Code and Angels and Demons; Tom Hanks plays him in the films) walking into a room and then declaring the answer to a puzzle that the reader could never have comprehended. It turned him into a human Google, and was incredibly dissatisfying. Not even an attempt to actual join some dots for the plot that can keep the reader engaged.
So yeah, utterly woeful, and I think to date the only book I've given one star to on Goodreads.