Dan Brown’s new novel is fun, if you’re willing to leave your brain at the door

There is a moment early in Dan Brown’s latest thriller, The Secret of Secrets, that feels as though it were lifted straight from a parody of his own work. Robert Langdon, Harvard professor of “symbology”, a word that does not exist outside Brown’s fictional universe, is walking through the misty streets of Prague when he sees a cloaked figure wearing a radiant crown and radiating a “stench of death.” Instantly, Langdon deduces this is no ordinary man, but the physical manifestation of a nightmare his girlfriend recently described. As a world-renowned expert in symbols, he interprets this as a prophecy. Without hesitation, he races back to their hotel, shouts for everyone to evacuate, pulls the fire alarm and then leaps...