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Dan Brown’s “Inferno”: Good Plot, Bad Science

The mad scientist is a dangerous stereotype -- an evil geneticist perhaps the worst.
The mad scientist is a dangerous stereotype — an evil geneticist perhaps the worst.

When Dan Brown’s latest novel, Inferno, was published last summer, several people insisted I read it – because it’s about an insane geneticist. So when my local library asked me to give a talk about a book with genetics in the plot, I chose Inferno. The talk is next week, and I had great fun marking up the book.

Dan Brown gets an A, as usual, for writing style. He keeps the reader turning the pages. But this time, the plot is a stretch, and he gets an F in genetics. (Warning: spoiler alert)

I learned that scientific accuracy shouldn’t get in the way of telling a good story at the Catalyst Workshop at the American Film Institute, where every summer a dozen scientists learn screenwriting from the pros. I went in 2005. After a week of dissecting The Day After Tomorrow, an exciting end-of-the-world thriller that seems all too possible with the recent crazy weather, we all concluded, as our instructors had said from the outset, that in entertainment, scientific accuracy just doesn’t matter. So it’s okay if the magnetic poles suddenly switch and a person recovers from septicemia in a few hours with one shot of penicillin. I love that film.

Tom_Hanks_as_Robert_LangdonAs anyone who’s read Dan Brown’s The Da Vinci Code and the Lost Symbol knows, protagonist Robert Langdon is a Harvard professor specializing in symbology who is summoned for emergencies that require him to rocket through Europe running from bad guys and heading off global disasters, while following clues and cues in art. He’s always called “Professor.” Many of my friends are professors, and I have an adjunct title myself, and we don’t call ourselves Professor. Maybe it’s different in the art world.

Having no time for anything other than math and science in college, I admit to being a dunce about the art part of the Dan Brown books. But I can comment on the science.


Robert Langdon (aka Tom Hanks) is reminiscent of Jack Bauer (aka Keifer Sutherland) in the TV series 24, in which incredible action unfolded over the course of a day. Inferno also takes place during a very busy day.

Due to the time pressure, Langdon’s metabolism is perpetually in high gear. Within a few pages, he was frozen in utter disbelief, startled, stunned, chilled, transfixed, he reeled, and did several double takes. I became concerned about his health when, in short order, his mouth fell open, heart raced, hair on his neck bristled, his pulse quickened, he sat speechless, audibly gasped, and barely breathed. Later on, his eyes went wide, as anyone’s would. His stomach knotted, he felt a visceral tremor, and his insides reverberated. Much of this happened whilst learning perfectly ordinary things about viruses, like the fact that they can nestle into our DNA.

Would my metabolism go into overdrive if I studied art? (Another of Brown’s very effective techniques is to put thoughts in italics.)

Poor RL. (I do like his initials. Me, Professor Langdon, and Ralph Lauren.)

Because the villain is a warped geneticist letting loose a human-gamete-eating virus, Inferno is also reminiscent of ContagionOutbreak, and The Andromeda Strain, the best of the genre. Actually The Hot Zone was best because it was true.

Illustration_for_Dante's_Inferno_by_Sandro_Botticelli_1481Inferno opens with a frighteningly vivid dream sequence based on artists’ depictions of Dante’s experiences in hell. Then RL awakens in a hospital room in Florence, tended to by a woman with a blond ponytail, Dr. Sienna Brooks, who gradually becomes just “Sienna” or Dantes_Inferno_Canto_28_“Ms. Brooks” while the other notables retain their titles. An obsession with feminine follicles emerges when we encounter a threatening “spike-haired woman” and the silver-haired head of the World Health Organization.

In addition to taking elements from 24 and the outbreak-type films, towards the end of the book, when the set-up is revealed, I was suddenly catapulted back to 1986 when Pam Ewing sees her supposedly dead husband Bobby in the shower on the TV show Dallas. Instead of introducing a surprise twin after actor Patrick Duffy quit and his character was offed and then he decided to return, the writers had Pam realize that her hubby’s death had been a dream, and the entire previous season, all 31 episodes, had never happened. (See Bobby Ewing in the Shower: An Epic Storytelling Gaffe).

Inferno has that feel of wasted reader time, especially when one is awaiting scientific details and explanations that never come.


(Dept. of Energy)
(Dept. of Energy)

The plot point that sets everything into motion is when “genetic engineer” Bertram Zobrist explains the exploding human population problem to WHO’s silver-haired leader Dr. Elizabeth Sinskey. I assume Dr. Z has a PhD — he’s described as a “genius of genetics,” whatever that means.

(An aside: I hate the term “genetic engineering.” It’s a media invention. You can’t major in it, and it isn’t offered in engineering schools. The only place I could find it as an academic field is in a few online programs from outside the U.S., and in the name of a publication I used to write for. However, Dr. Brooks declares, “The world of genetic engineering is one I’ve inhabited … for many years… Perhaps she took the online course.)

Anyway, Dr. Sinskey doesn’t take Dr. Zobrist’s predictions seriously, perhaps because he is all gloom and doom with nary a mention of the “carrying capacity,” the leveling off of population expansion rather than annihilation of humanity.

So Dr. Z. hires a shady organization called the Consortium, led by the shady “provost,” which is headquartered on a big yacht full of mysterious bad guys and the spiky-haired woman. The Consortium is to shield him for a year as he invents and plants a viral plague to control population growth, without asking any questions.

Yersinia pestis, the cause of the Black Death.
Yersinia pestis, the cause of the Black Death.

Dr. Zobrist, it turns out, is a big Dante fan, and Dante died of bubonic plague. This is when I became intensely interested, having been criticized for writing an article for The Scientist on the plague genome, with a sidebar on using it as a bioweapon, just weeks after 9/11. (I also got in the mail at that time a letter from Libya that the FBI yanked as a possible anthrax missive.)

A plague story! Alas, Inferno evokes “plague” rather loosely. Somehow the plague bacterium that felled Dante along with a third of Europe during the Middle Ages morphs into an airborne viral infection in the novel. I’m not sure why.

Dr. Sinskey taps RL to find the bioweapon, because clues lurk in Sandro Botticelli’s depiction of Dante’s Inferno and other works. Snippets of the puzzle struggle to the surface of Langdon’s consciousness as he and Dr. Ponytail schlep through the art and artifacts of Florence. It would have helped the good Professor immensely, and saved at least 100 pages, if he owned a smartphone and didn’t have to bug tourists to use their Internet connections to look up the parts of Dante’s tome that he can’t recall.

Meanwhile, European CDC guys join the chase. Here is a good website for artistic clues and maps, if you’re like me and are just waiting for the science to show up.

Red_Herring (2) The plot detours to a few red herrings, which are jarring and manipulative. Dr. Brooks doesn’t really have a ponytail, it’s a wig; she’s bald from the lingering stress of having been raped. Dr. Sinskey isn’t really being drugged against her will when RL spies her slumped over in the back of a car; she has a barf disease that requires sedation. And finally, imposter Jonathan Ferris doesn’t have plague, he has a latex allergy from wearing a mask to play a character that appears earlier in the book. Also, good guys are bad guys and vice versa.


Human_brain_female_side_viewEarly foreshadowing of superficial science is on page 36, where the author confuses cerebellum with cerebrum, and PET scans with CT scans. And he makes the classic trio of errors later on — human cell walls (animals are the only types of organisms without cell walls), “a bacteria,” and each of us having our own genetic codes (the correspondence between RNA codons and amino acids is universal, a mistake even in this week’s New Yorker article about genetics in China. We have individual genome sequences.)

But the worst illogic comes towards the end.

Tethered beneath the surface of a gloomy underground lagoon, not in Italy, lies a bag filled with yellowish-brown goop that holds enough of a mysterious virus to render much of humanity infertile – somehow. The investigators have set up PCR devices throughout the area, which all start blinking red to indicate detection of the “never-before-seen viral pathogen.” What did they use for primers? You can’t amplify a nucleic acid using the polymerase chain reaction without having a smidgeon of DNA or RNA from known pathogens.

Another error is one of omission. Sprinkled throughout the book are mentions of germline manipulation; Dr. Z. is a “germline genetic engineer.” We learn that fooling around with a germline is evil and powerful, but not exactly what it is. And herein lies the confusion. To a biologist, “germ” means “germ cell,” as in precursors to sperm and eggs. To a normal person, however, “germ” means a pathogen, such as a bacterium or virus. So it isn’t clear that a germline manipulation actually means changing future generations. And germline manipulation won’t even be necessary, because if the viruses work, there won’t be another generation. They need only obliterate existing sperm and eggs.

Sperm-20051108Practically, I had difficulty envisioning how the airborne viruses would get into gametes of the hundreds of people pushing to escape the lagoon, like Christmas shoppers barging into Wal-Mart. Germline manipulation isn’t easy. It’s banned in people for ethical reasons. In fact a gene therapy trial, for hemophilia, was temporarily suspended when altered genes turned up in participants’ semen, but luckily they were in the seminal fluid, not the actual sperm cells. Germline manipulation is used, however, to create animal models of human disease.

Fortunately, Dr Z’s scourge won’t drive humanity to extinction, because a few people are randomly immune to the virus. Random? How does that work? Wouldn’t a resistance genotype be quite specific, invented by those engineers, and not random?

Most vexing was the unfamiliarity with the ways of viruses. For example, the supposed experts in Inferno use the term “vector” as if it is a type of virus, like a herpesvirus.

128px-Biohazard.svg“Vector” is a general term that means a vehicle to transfer DNA. Proclaims Dr. Brooks, “A vector virus … rather than killing its host cell … inserts a piece of predetermined DNA into that cell, essentially modifying the cell’s genome.” I don’t know what predetermined means (viruses can’t think), and a virus inserting into a chromosome, a phenomenon called lysogeny, doesn’t modify a DNA sequence, it adds to it. And it’s normal. Our chromosomes carry loads of viral sequences.

Still, “Langdon struggled to grasp her meaning. This virus changes our DNA?

Alas Drs. Brooks and Sinskey can’t fathom how to counter the virus, other than making another virus to fight it. Antisense? RNAi? Biotechnologies to silence genes have been around for decades. One paragraph describes gene therapy, not calling it that, and claiming it’s new. It isn’t. The first clinical trial was in 1990.

The_X-Files_title_logoThe lack of savvy about viruses may be due to a Dana Scully effect, the assumption that any medical doctor is also a scientist. (She was from the X-Files, an MD constantly calling herself a scientist.) The three technical experts Dan Brown thanks in the preface are MDs – two are infectious disease specialists, the third I couldn’t find, and none belong to the American Society of Human Genetics. He needed to run the genetics parts by a geneticist. I would have happily done it.

Evolution is also handled oddly, although RL claims to be skilled in matters Darwinian. He and the docs confuse natural selection and survival of the fittest, which deal with reproductive success, with genetic enhancement to “advance the species” and “create better humans.” I think Brown means that those who survive to have successful sex after the viral scourge will then, either by the viral DNA or some new genetic treatment, churn out kids who get high SAT scores and humanity will be saved. The long-awaited explanation of the science is delivered in a style I call hand-waving — throw out a bunch of terms that presumably readers won’t recognize to make it sound like it makes sense. It doesn’t.

Even the conclusions in plain English are vague to the point of meaninglessness: “He had unlocked the evolutionary process and given humankind the ability to redefine our species in broad, sweeping strokes.” From a virus with a predilection for gametes?

Finally, the fake-ponytailed Dr. Brooks, flummoxed by the ins and outs of viruses, assures us that “the human genome is an extremely delicate structure … a house of cards.” Then how can engineers manipulate it with a whiff of a virus?

It’s great that a novelist as acclaimed as Dan Brown would base a plotline around genetics. But he squandered an opportunity to teach the public about the good that geneticists do. Why not a subplot of a sick kid? A family that uses the terrifying “germline genetic engineering” to vanquish a terrible genetic disease?

The last thing our science-phobic world needs is another mad scientist – even a fictional one.

  1. I found another mistake. My 6th grade students could have told him that a virus doesn’t deposit its DNA into human host cells (or animal cells) through the “cell wall” because our cells don’t have one! Nevertheless, the book was fun to read and I did learn about art and Dante!

  2. Yes, I left out the cell walls to save space. He made the big trio of errors — human cell walls, “a bacteria,” and my favorite, the good old human genetic code. Even the New Yorker article about BGI this week made that error. It is used when “human genome sequence” is meant. So as a result, much of the non-nerd public thinks we all have our own personal genetic codes. I stopped writing about this because people tell me I’m wrong, but I’m not. The code is the correspondence between RNA codons and amino acids, as of course you and your sixth graders know, and if we each had our own all that genetic engineering couldn’t happen. I know, I know, the meaning of code has changed. But in my textbooks, when I go through the history of deciphering the code, demonstrating universality, I can’t just turn around and talk about everyone having their own. Phew. Thanks for listening!

  3. Dear Professor,

    I am a little worried, that according to your knowledge, only the novel’s solution for the population problem is not possible, and the problem itself is real.
    So we are doomed… 🙂

    Greetings from Hungary,

  4. Hi Andras, great comment. Inferno’s coverage of the population problem I thought was the best part of the book — as far as I know accurate, and yes, scary. Dan Brown is very good, in this area, of showing both viewpoints. You read about the maniac scientist, and realize he isn’t 100% bad, that to an extent, he’s got a point. I should have written that — the basic premise is quite valid and interesting.

  5. Great review! If I had to recall how much I laughed when reading this book. When the PCR machines started blinking I was laughing so loud people around me must have thought I was crazy.

  6. How about something even more simple. No medical professional with enough intelligence to pass boards (medical, pharmacy, nursing… Take your pick.) is going to use a topical antihistamine for an allergic reaction serious enough to cause blisters and “labored” breathing. At the very least he would be taking oral diphenhydramine and probably an H2 blocker as well. Of course anyone who has experienced a severe allergic reaction should carry an Epi-Pen or similar product, and as a physician he would possibly even carry oral steroids.

  7. Factual error. Hagia Sophia was built by Justinian in 517 not in 360 as stated in the book. There might well have been a church on that spot in 360 but it wasn’t the present day church.

  8. I was disappointed you wrote such a long review without addressing the validity of the science of the key issue raised in Inferno: overpopulation of the earth and the dwindling supply key resources such as clean water. I believe nitpicking the fictional genome science while ignoring the key storyline issue was a disservice to Brown.

  9. I did not intend to write a general book review, certainly there are plenty of them. In contesting the coverage of genetics/genomics, I was just sticking to the topic of this blog and my own expertise. Someone commented on the underlying premise, and I agreed that the population biology seemed accurate. But to state that wouldn’t make for very compelling blogging. Also, I could only appreciate the very nice coverage of population biology until I got to the parts where the supposed experts are so shocked at learning that a virus can insert into a human chromosome, or getting PCR so wrong. I try hard to stick to the topic of DNA science.

  10. I was wondering about the figures given in the book about the virus. They say that the crazy geneticist was trying to make about 1/3 of the population of the world infertile but wouldn’t that mean that far more people would be prevented from reproducing? If 1/3 of every generation from that point on was infertile the odds of two fertile people coming together are also lower and that would risk extinction in a few generations, right? You’d think a brilliant geneticist would have thought of this and at least one character in the book would have mentioned the problem.

  11. I wondered about this too. The earlier discussion of population curves was quite well done, but at the end it just got silly, the characters not seeing the obvious. It almost seemed to me as if the author was up against a deadline and hurried the ending without giving it the careful thought of the earlier passage — that does tend to happen. Thanks for your comment.

  12. I did not finish the book. I loved the Da Vinci Code and couldn’t put it down.
    I found Inferno plodding and the chase scenes unrealistic and implausible.
    I loved the Hot Zone and Andromeda Strain but this book Inferno did not measure up to what I would call “a good read” a rare and wonderful commodity in my experience.

  13. So according to your previous comments, can I conclude that a ‘randomly infecting’ disease, wiping out some people’s fertility is impossible? Say it does become a legitimate option to fight overpopulation, do you believe we should put it to use?

  14. I don’t see how it could be random. There would have to be exposure, and then genetic susceptibility. I wouldn’t put such a thing, if it existed, to use. It isn’t up to me to decide who should and shouldn’t reproduce.

  15. Absolutely. Several technologies silence specific genes, and it happens in our bodies all the time. Google RNAi, antisense, CRISPR. The gene is the instruction — but it is either expressed or it isn’t.

  16. I would like to regard the novel more as a funny travel around the wonders of Art World rather than a hotch potch discussion on Virus and genetic engineering!

  17. 9 years later and a few changes to the book, might make it better (mRNA instructions, Vaccine, cabbal of NWO evil guys, etc)

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