To say that Dan Brown's Origin is one of the worst "thrillers" ever published would not be accurate. Not because it is not appallingly, insultingly, groan-inducingly written — it is — but because it is not, in fact, a thriller.

It would be hard to pinpoint the exact moment at which I made this discovery, but I would venture a guess that it was somewhere around chapter three. The clues, like the endless codes Brown's characters are doomed to chase fruitlessly around a version of Europe that rarely achieves a CIA World Factbook entry level of descriptive interest, are everywhere — hiding, as he might put it, in plain sight.

Robert Langdon, a professor in a non-existent field called "symbology" that seems mainly to consist of knowing things like what an ampersand is, is ostensibly Brown's dashingly cerebral but relatable hero. What he really is, though, is a stand-in for Brown himself. Every sentence in this book is imbued with Brown's fascinating perspective as a reasonably fit gazillionaire naif whose main hobbies seem to be high-end non-commercial aircraft and food. You can see it in the way he forces his characters to have thoughts like "Langdon had always enjoyed the challenge of modern art," a sentiment no one has ever expressed without a glass of shiraz and something highbrow, perhaps "18th-century composer" Ludwig van Beethoven, on the Bose.

(Yes, Brown really does seem to be under the impression that his readers will not have heard of this obscure figure. Ditto "Nicolaus Copernicus … the father of the heliocentric model — the belief that the planets revolve around the sun — which ignited a scientific revolution in the 1500s"; "Friedrich Nietzsche, the renowned 19th-century German philosopher and atheist"; and "Winston Churchill himself, the celebrated British statesman who, in addition to being a military hero, historian, orator, and Nobel Prize-winning author, was an artist of remarkable talent.")

Brown is also keen to remind us of Langdon's "faithful daily regimen of swimming laps" and dares us to believe that this shy 50-something academic is capable of performing spontaneous rib-crushing tornado kicks and spur-of-the-moment foe-stunning piledrivers.

Brown thinks that a "classicist" is someone who likes old things rather than a scholar of classical languages, that Harvard professors of subjects real or imaginary say things like "Nostradamus was the most famous prognosticator of all time," that it would cost untold billions to create a computer with the epoch-making ability to tell you what the Dow closed at on August 23, 1974, that there exists a "priceless manuscript," as opposed to a paperback book, entitled The Complete Works of William Blake, or that this or any manuscript has standard page numbers. Page numbers are in fact a major pitfall for Brown, at one point leading me to wonder how many books he has actually opened in his life, let alone read:

"It's a clever decoy." "You've lost me," Langdon said, eyeing the painting. "Edmond chose page 163 because it's impossible to display that page without simultaneously displaying the page next to it — page 162!" [Origin]

Reader: If you ever come across a book in which it is possible to "display" page 163 without also displaying page 162, write to the publisher. You are almost certainly due a refund of some kind, to say nothing of an explanation.

Brown is I daresay on much firmer ground when he sticks with telling us the make and model of well-nigh every vehicle driven by each character in the book, or when helpfully informing us on multiple occasions that the first of many helicopters in which his characters travel is an "EC145" (is that like an F-150?). His approach to describing a very large room is to compare it to "an airplane hangar" and to specify the square footage (34,000!). One character who has "collected a wide array of priceless impressionist and modern art" is also said to be the proud owner of "an oversized smartphone — one that he had designed and built to serve his own unique needs" and to enjoy having conversations "over a plate of short-rib crudo at Boston's Tiger Mama." '"White flip-flops are couture?'" asks the befuddled Langdon. "'Flip-flops?!'" cries his interlocutor. "'These are Ferragamo Guineas.'"

Let's be clear, though. Despite the exotic locales in which he insists on setting his books — Paris, Venice, Madrid, Barcelona — no one could ever accuse Brown of being a cosmopolitan. To him it seems perfectly reasonable that a stock English character should be named "Winston" and have a voice that sounds like Hugh Grant and say things like "Righto." (Thank goodness "Winston" turns out to be a robot.) When Brown wants a Muslim character to be from somewhere, he quickly settles on Dubai and shows no sign of regretting it even when it starts to make his chronology look iffy.

Once you have cracked the code, as it were, it all starts to seem obvious. The dust jacket is a tease. Origin is not a thriller. No writer honestly attempting to concoct one would dare to begin with several chapters of a man taking a guided tour of a museum complete with unevocative descriptions of each work of art and follow it up with such varied set pieces as a conversation in a boat, a conversation on a plane, and a conversation in a driverless Tesla SUV before settling in to two more long conversations in an apartment and an office building. There are no real chases here and only two gunshots. An author attempting to claim the mantle of Robert Ludlum, however incompetent, would never interrupt what almost amounts to a tense chapter with such bizarre interior monologue fare as "Atheists now have their own baseball caps?" or, in the middle of a helicopter search, interrupt the parody of an action scene taking place to inform us that Spanish police helmets might have inspired those worn by the Stormtroopers in Star Wars. No actual writer of this kind of fiction would ever compose any of the following sentences and paragraphs (taken at random and willfully ignoring many similar offerings):

The Dawkins classic The Blind Watchmaker forcefully challenged the teleological notion that human beings — much like complex watches — could exist only if they had a "designer." Similarly, one of Dennett's books, Darwin's Dangerous Idea, argued that natural selection alone was sufficient to explain the evolution of life, and that complex biological designs could exist without help from a divine designer. [...] The holy seat of the Roman Catholic Archdiocese of Madrid — Catedral de la Almudena — is a robust neoclassical cathedral situated adjacent to Madrid's Royal Palace. Built on the site of an ancient mosque, Almudena Cathedral derives its name from the Arabic al-mudayna, meaning "citadel." [...] Madrid's Palacio Real is Europe's largest royal palace as well as one of its most stunning architectural fusions of classical and baroque styles. Built on the site of a ninth-century Moorish castle, the palace's three-story facade of columns spans the entire 500-foot width of the sprawling Plaza de la Armería on which it sits. The interior is a mind-boggling labyrinth of 3,418 rooms that wind through almost a million and a half square feet of floor space. The salons, bedrooms, and hallways are adorned with a collection of priceless religious art, including masterpieces by Velázquez, Goya, and Rubens. [Origin]

How many rooms again?

Nor would the most plodding and tired hack, as opposed to a quasi-professional soul searcher, write dialogue like this: "'The human brain,' Edmond declared. 'Why does it believe what it believes?'" (Thank goodness Brown gets around the problem of writing conversations that sound like they could possibly have been spoken by human beings via the nifty device of putting approximately one-third of the book's dialogue in the mouth of a talking computer.) A few chapters later, we come to what would appear to be a crisis, a moment of extraordinary tension and gravity, with Langdon standing indecisively like Indiana Jones over the gaping chasm into which the Holy Grail has just fallen. "'Robert,' Ambra whispered, 'just remember the wise words of Disney's Princess Elsa.' Langdon turned. 'I'm sorry?' Ambra smiled softly. 'Let it go.'" (The "it" in question is Langdon's cellphone.)

Nor, finally, would anyone who is not going out of his way to subvert the very notion of suspense as a factor that might conceivably motivate us to turn pages attempt even as a joke what must be the most banal chapter-ending cliffhanger in the history of fiction: "'This getaway car was hired,' Langdon said, pointing to the stylized U on the windshield. 'It's an Uber.'" Nor would he dream of opening the next chapter by announcing that a police officer has responded to this utterance with "a look of wide-eyed disbelief" at "the quick decryption of the windshield sticker." Decryption! Code-breaking! Rare feats of professorial intellect, like knowing what corporate logos are! Imagine what further wonders Langdon might perform if only his creator allowed him to visit a certain international hamburger chain or glance down at the anagogic white fruit staring up from the bottom of his cellphone. (Unimprovably, Brown follows up this masterclass in symbology from Langdon by noting himself that "Uber's ubiquitous 'on-demand driver' service had taken the world by storm over the past few years. Via smartphone, anyone requiring a ride could instantly connect with a growing army of Uber drivers who made extra money by hiring out their own cars as improvised taxis.") If this guy is trying to write thrillers, then this article is actually a piece of SpongeBob Squarepants fan fiction.

Whatever else you want to say about Brown, he is certainly a memorable writer. He takes what might be charitably described as a loose view of the relations between nouns and verbs, subjects and predicates, between words in general. He prefers his metaphors shaken and stirred, sluiced, juiced, and served as a teeming froth of impossibilities: We learn of a "collage" of "symbols" that, he tells us, "flooded the sky" (how could you make them out with all the waves crashing above your head?), a purportedly controversial lecture being compared to "a flaming spear" tossed "into a hornets' nest" (so that when it falls in addition to having pissed-off hornets you can burn your lawn?). Taking no heed of such would-be pressing concerns as making us care about his protagonists or their missions, he instead goes out of his way to specify, inter alia, that Luis Ávila is a "navy admiral" (as opposed to the army or an air force kind, presumably) and that a character who is not smoking has just "exhaled," of all things, "a breath."

Instead he writes sentence after sentence that will elicit a groan from any moderately educated reader but which probably seemed quite plausible to the author, viz., "Langdon had tasted Montrose only once, in an ancient secret wine cellar beneath Trinity College Dublin, while he was there researching the illuminated manuscript known as The Book of Kells." There are indeed wine cellars in most universities in the British Isles, but they are hardly secret, being opened on numerous formal and informal occasions, their contents shared even with undergraduates. And why would Langdon go all the way to Ireland to see this medieval copy of the Gospel when anyone can access a facsimile of it online or purchase a printed one with a detailed scholarly apparatus? Is he a textual critic now rather than a vague generalist? No, but it's a book with "symbols" in it, you see, and a chance to use the words "ancient" and "secret" in the same sentence.

The novel's most crucial scene is the stunning almost-but-not-quite-too-late moment when, having reached as far as he can into the depths of his (as is repeatedly impressed upon us) encyclopedic memory, it dawns upon Langdon, purportedly a member of the Harvard humanities faculty, that "Blake was not only an artist and illustrator … Blake was a prolific poet." Bingo? This is like saying that John Carpenter is not only a composer of synthesizer music, he is also the director of such classic films as Halloween and The Thing.

What makes Brown such an enticing specimen is that this former high-school English teacher never gives you the impression of having encountered, much less absorbed, the most elementary rule of prose writing, one that is being repeated mantra-like in classrooms as you read this — namely, "Show, don't tell." Brown is incapable of showing. (He is no great shakes as a teller either.) This is how it is possible for him to give us a man who has just witnessed the murder of a friend feeling this in his heart of hearts: "There will be time to mourn, Langdon told himself, fighting back intense emotion. Now is the time for action." This is why Brown also resorts to marketing language ("ultrasleek office space"), why he opens chapters with obvious pastiches of websites like WorldforTravel.com, why his idea of describing architecture is to visit the Wikipedia page for a building and quote all the accolades compiled there and borrow without attribution the description from a New Yorker article that he later decides to quote directly after all. Elsewhere, we are told, "Langdon's eidetic memory quickly conjured the alchemical symbol for amalgamation." Is this how memories work, eidetic or otherwise? I find it difficult to believe that anyone whose ears are accustomed to the rhythms of English, written or spoken, could write of a character's hope "to move past her dark past." How did this make it on the page? Are Brown's editors intentionally trying to sabotage him?

There is one more thing worth pointing out about Brown: For a writer whose plots tend to settle in the obscure byways of religion, he seems remarkably unaware of even the most critical and well-known facts about his chosen subject. There is, in fact, scarcely a sentence in the book bearing upon the Roman Catholic Church that is free of error. (To mention three examples among dozens: There is no such office in the Catholic Church as "head priest" or "presiding clergyman;"; laypeople do not read the Gospel at Mass, nor are the readings themselves chosen at random by the celebrant.) Would it have been totally beyond the resources of the world's largest publishing concern to correct Brown's errors in a book whose first page contains a pompous disclaimer attesting to the "truth" of all the novel's religious content and whose final pages contain his no-doubt sincere acknowledgement of generous assistance from dozens of editors, researchers, and fact-checkers?

Brown's howlers are insulting in themselves, but they point to a larger issue, namely his own absurdly condescending view of religion and its adherents. Brown clearly thinks that religious people confronted by a weirdo tech entrepreneur in black jeans who says that his secret computer program "proves" that God does not exist would murder him with bullets from a 3D-printed gun concealed inside a gigantic metal rosary (yes!) rather than smile blandly and walk to the other side of the street. Christians hear such preposterous claims every day, though usually from people who don't talk like this: "'Do you hear that sound?' Edmond called over the booming rapids. 'That is the inexorable swelling of the River of Scientific Knowledge!'" Somebody save us from drowning.

Dan Brown is a truly terrible writer. But I would be lying if I said I hated reading Origin. I did not. Few books have ever given me a more vivid impression of the writer or struck me more with the force of their truthfulness. The present volume provides as clear a window into its author's soul as the Confessions of St. Augustine or Proust's Remembrance of Things Past. This was hardly what I expected, but that's what happens sometimes when you open books, including those with both left and right-hand pages.