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Publisher's Summary

When the NSA's invincible code-breaking machine encounters a mysterious code it cannot break, the agency calls its head cryptographer, Susan Fletcher, a brilliant, beautiful mathematician. What she uncovers sends shock waves through the corridors of power. The NSA is being held hostage, not by guns or bombs, but by a code so complex that if released it would cripple U.S. intelligence. Caught in an accelerating tempest of secrecy and lies, Fletcher battles to save the agency she believes in. Betrayed on all sides, she finds herself fighting not only for her country but for her life, and in the end, for the life of the man she loves.
©1998 Dan Brown (P)2004 Books on Tape, Inc.

Critic Reviews

"In this fast-paced, plausible tale, Brown blurs the line between good and evil enough to delight patriots and paranoids alike." (Publishers Weekly) "Digital Fortress is the best and most realistic techno-thriller to reach the market in years....A chilling thrill a minute." (The Midwest Book Review) "Exciting...will rivet cyber-minded readers." (Booklist)

What members say

Average Customer Ratings


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  • Overall


I enjoy reading Dan Brown; I find his books are based on interesting ideas and concepts, and Digital Fortress is no exception.

I noted in my review of "Angels and Demons" that Brown's story-telling improves between that book and "The Da Vinci Code". "Digital Fortress", written before "Angels and Demons" further proves that sentiment. Heather from Fullerton's comment that it's "not quite as sophisticated" is spot on.

The book starts off well enough, and it was ticking along fine until towards the end, when the characters - and therefore the story line - seemed inexplicably struck dumb.

I read this book basically because it's written by Dan Brown, and I was curious to see what else he has written; as I said off the top, I find the ideas and concepts he writes about quite interesting.

But if you're debating whether or not to get this book, I would say spend your money on something else - even another (later) Dan Brown book!

53 of 56 people found this review helpful

  • Overall

Don't try it

One of the worst books I've ever read. The technological background is not weak, it's ridiculous. Anyone that has a minimum understanding of software engineering will find difficult to finish the book. Cryptography-related descriptions and explanations are childish. The plot is paper-thin, character motivation is unbelievable...

21 of 22 people found this review helpful

  • Overall

Don't read what you know

Let me start by saying that I really enjoyed Da Vinci code and its prequel, so I was optimistic about this read. Unfortunately, I was horribly disappointed. I am not sure if the culprit is Mr. Brown's lack of knowledge about this subject (compared to the subject matter of Da Vinci) or my relative depth of knowledge about it (I happen to run data centers for a living) but I was extremely disappointed in the book.

The characters were interesting and the basic concept to start with was OK, but from there it degenerated rapidly. By the end of the book I was figuring things out quicker than most of the characters (always a bad sign) and the majority of the plot line had become completely unbelievable. As with all techo-thrillers, the bottom line is that when the machine is run-amok or in horrible danger... simply turn the thing off. Since this solution is so elegantly simple, writers from Asimov to Star Trek have been inventing convulted ways to keep their machines from being turned off, and even more convulted reasons why those mechanisms would be built. Just in case Mr. Brown decides to write in this genre again, here are some good rules of thumb:
1) Rule #1 of data center design - The EPO (emergency power off) is always located at a controlled and secure location near the exits (there can be multiple, after all) to the data center... not 3 stories below the data center in some goofy catacombe of generators and cooling equipment.
2) Rule #1 of computer system design - If your $3 billion computer runs so hot it can explode... put a $10 temperature sensor in it so it can shut itself down to keep that from happening accidentally.
3) Rule #1 of being an international assassin - silencers don't work very well on revolvers, sound escapes from between the cylinder and the barrel.

32 of 35 people found this review helpful

  • Overall
  • james
  • Hartselle, AL, United States
  • 10-11-10

Geniuses should be smarter than this.

Audible had a deal on this title and I was curious to see if Brown's writing was worth the incredible hype surrounding him so I gave it a try.

As for the style of Brown's prose: it's entirely adequate, but nothing exceptional or even distinctive.

As for plot: Riveting, but far from believable. Plenty of deus ex machina and unlikely coincidences balance stupid decisions made by the characters. I'll give him credit for making all parties equally fallible yet insanely lucky.

The climax was hard to listen to, not because it's very tense (which it is) but because the tension is for the wrong reason. They need a code and have a clue to finding it. I don't have a background in science or history, but the minute I heard the clue the answer is instantly (and blindingly) obvious. Yet we're supposed to believe that a brilliant cryptographer, a genius software coder, the Director of the NSA, and a room full of others take nearly 15 MINUTES to figure it out?

It's paced well and makes you want to see what happens next, but as with so many other thrillers the cookie-cutter writing and characters like the supermodel cryptographer and the action hero linguistics professor make it seem like an otherwise good book dumbed down for the best-seller market.

4 of 4 people found this review helpful

  • Overall
  • Scott
  • Seattle, WA, USA
  • 09-20-06

Don't buy

I wish I had read the other reviews before buying this book. I'm a fan of Dan Brown's other books but this one is pretty bad for all the reasons mentioned in the other reviews. If you know anything at all about computers or math, turn your brain off as you read.

Btw if you do manage to get through the book, do yourself a favor and skip the last half hour or so. Reading the painstaking walkthrough of a google search and all the breathless "deductions" the characters go through nearly drove me to a life of crime.

14 of 16 people found this review helpful

  • Overall
  • Irene
  • Sanford, NC, USA
  • 05-22-05

Not that Bad

Although some have gave this book a poor rating - the book is not that bad. When you have read enough books the plot in this was easily solved and not much guess work; however the story was good and still enjoyable. It kept my interest and that's important.

4 of 4 people found this review helpful

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  • Shannon
  • Newton, MA, United States
  • 09-08-08

Suspend reality

If you know ANYTHING about computer science then you'll need to be able to COMPLETELY suspend reality in order to enjoy this. I was not able to.

8 of 9 people found this review helpful

  • Overall


Da Vinci Code was always tantalizing - it kept you starting the new chapter. This book is so predictable that it is tiresome. I listened to the unabridged version in honor of Da Vinci Code. What a waste of my time. Save yourself the aggravation. The final code was so obvious I predicted it as soon as I read the description of the riddle. Then the most brilliant cryptographers in the world spent pages trying to solve it. Boring. Brown is trying to be too cute and has no new tricks in this book.

6 of 7 people found this review helpful

  • Overall
  • Kathleen
  • North Scituate, RI, USA
  • 04-09-05

Skip It

I really enjoyed the DaVinci Code and Angels and Demons -- but, the talent seen in those books was not visible in this effort. The characters were cookie-cutter stereotypes, the plot was a misery and the technical details inaccurate. Save your book credits for Mr. Brown's later works.

5 of 6 people found this review helpful

  • Overall
  • Josh
  • Santa Monica, CA United States
  • 07-18-04

PREDICTABLE - You are smarter than this book!

I liked Da Vinci Code and Angels and Demons; this work was not nearly as good.

One of the things I liked about the other series is the assortment of trivia that permeates the story. I didn?t find the factoids about cryptology or the NSA conspiracy theories as compelling. This, however, is a minor flaw.

The big problem with this book is that I found it sooooooo predictable. Within the first 2-3 hours of the book, I had figured out the mastermind/villain twist. Much worse was the ending, where the characters agonized over a code for 15 minutes that I had mostly deciphered upon hearing. It?s pretty unsatisfying to be that much smarter than the NSA cryptologists.

If you are a Dan Brown fan, it is worth a listen. I finished the book, which is much better than I can say for a few books that I have downloaded. On the other hand, I have listened to much better.

2 of 2 people found this review helpful

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  • Roy
  • 07-26-06

Bad Science Bad Writing Bad Book

But well read the two stars ar eentirely for the naration if the reader had been less skilled I'd have given up. If I'd been trying to read it I'd probably have burned the book and given thought to burning Dan brown as well.

So what's so bad.

It starts okay, the characters are cliches genius linguist in the Indiana Jones mold (yes I know he was an archeologist) meets genius cryptographer that looks like she stepped off a catwalk (Jessica Alba would probably play her in the movie she's very smart but never uses those brains for anything.)

Any way they hook up and fall in love then get involved with a secret government project to secretly decript everyones e-mails. (this isn't really a spoiler you get this much on the back cover)

Okay so the action moves on for reasons tha tonly become apparently late on and don't really work the hero is sent to France to get hold of a mcguffin. Meanwhile the gf is set to do clever things with computers in an I.T. section where RSI is the least of her worries.

Okay so the plots bad and cliche, the characters aren't even cardboard they're paper thin and the environment are'ne hugely exciting even a cool IT suite is still a set of desks with a pc on the top.

Coincidence piles on coincidence on a large wobbly stack that is neither structurally sound or that interesting to watch being built.
Supposedly clever people act stupidly and miss things even the reader (who''s meant to be a lot less bright than these guys) has figured out and then the hero well meaing untrained amatuer that he is points out of all the things in this book this constant making everyone dumb so the hero seems start is the most irritating.

For the author and the book no stars for the reader 2 stars for heroic efforts at turd polishing.

15 of 19 people found this review helpful

  • Overall
  • Jeremy
  • 11-29-11

A good read for geek thrill seekers.

I enjoyed the concept of book, although a plot line was a touch predictable. I would have like to have seen a little character building.
None the less I found I really enjoyed it.

1 of 1 people found this review helpful

  • Overall
  • Tim
  • 03-05-11

Don't believe the critics!

Despite what the poor reviews say, this book is not as bad as most people make out.

Yes, it has the typical Dan Brown flaws - poorly verified facts, a tendency to be glib and a mostly predictable plot. Still, there are enough twists to make it an interesting yarn and some good charactors.

I also absolutely love the epilogue where Ensei Tankando's dad has to bury him - it reminded me Theoden in the Two Towers. The depiction of the obnoxious little punk is also quite good, and you almost feel he deserves his fate (almost...)

Anyhow, if you're after a bit of light listening / stg for the trip to work, you could do worse than this book although do try 'Angels and Demons' 1st...

2 of 3 people found this review helpful

  • Overall
  • Andrew
  • 11-07-10

recommended reading

a different direction from Dan Brown but still a very good listen.
If you like Dan Brown's books you will enjoy this

2 of 3 people found this review helpful

  • Overall
  • William
  • 10-24-05

Unbelievably Bad!

This book is laughably bad!

From the corny hero decription 'seven foot tall with a rugged jaw and stealy blue eyes' etc, you know the kind of cliche drival at the start of the book, to the assassin who goes around killing characters for absolutely no reason midway, finally to the ridiculous end - five letter password - the baddy who's in love with Susan the heroin - can you guess the password?


14 of 26 people found this review helpful

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  • Julie Evans
  • 10-03-17

Brilliant read

Dan Brown never fails to deliver Digital Fortress is no exception suspense intrigue romance brilliant

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  • splash
  • 09-02-17


Dan Brown is more famous for his novels that have turned into blockbusters, but for me this is one of his best. The author as always works hard on research to pack the book full of data relating to the plot. the concept of the story is clever, complex enough to allow for numerous twists and just leaves you in awe of how it is all pulled together. This is a brilliant book and would be in my all time top ten. Great narrator too.

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  • marianne
  • 08-05-17

Not usual standards

bit dull and story, I felt, takes it's time to get going or even what story was about. Not to his usual standards sadly but good holiday read.

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  • Andrea Lee
  • 03-17-17


Loved the story and the narration was brilliant and keeps you interested but all Dan brown books are amazing

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  • smithpaddy
  • 03-12-17

thrilling but awful ending

typically enthralling story from Dan Brown, excellently twisting and surprising. But the ending was so weak. just when you thought it couldn't get more cringe, it did

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  • andy
  • 10-27-17

Excruciatingly boring

The plot was predictable, but unlike other Dan Brown books it advances achingly, labouring over small details again and again despite their obviousness. As usual with most fiction works the IT references are hilariously inaccurate. This seems to be a book with no effort or research put into it.