The book is thoroughly hostile to religion in general and the Catholic Church in particular. If you can get past that and forgive its self conscious pomposity and absurd caricatures rather than characters, and insertion of irrelevant political correctness subplots, then you got a reasonable high tech thriller while not that thrilling and your nails will remain unbitten, it passes the time.
It starts off with the mystery of a world changing discovery by a reclusive genius who is also a bitter atheist and computer genius and great friends of Robert Langdon, our utterly insufferably evaporative hero. It’s centered in Spain, Barcelona mostly, and one is treated to a travelogue of famous sites with typically liberal-left commentary of dubious charm along the way.
The plot has the typical elements of a Dan Brown novel, with his typical assertion that all is true but then serves up some things not at all true, though not as glaringly egregious as his other novels which essentially slander the Catholic Church. One minor example is a quote by Churchill that is one widely misattributed to him and Brown doesn’t seem to know it. William Blake shows up and is mischaracterized as well, though that’s somewhat necessary to shoehorn him and his poetry and art into the plot.
The big payoff, because of the hype in the build up, isn’t quite as rich as one might expect, but it really couldn’t be with the cosmological, theological, and teleological doom that Brown implies. Big subjects are treated here, and some surprises show up, but it’s hard to forget just how mean spirited Dan Brown is as he plods Landon through his brain teaser puzzles.