Digital Fortress Read online

  Digital Fortress

  Dan Brown

  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 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.

  Dan Brown

  Digital Fortress

  Prologue

  Plaza De Espana, Seville, Spain, 11:00 A.M.

  It is said that in death, all things become clear; Ensei Tankado now knew it was true. As he clutched his chest and fell to the ground in pain, he realized the horror of his mistake.

  People appeared, hovering over him, trying to help. But Tankado did not want help-it was too late for that.

  Trembling, he raised his left hand and held his fingers outward. Look at my hand! The faces around him stared, but he could tell they did not understand.

  On his finger was an engraved golden ring. For an instant, the markings glimmered in the Andalusian sun. Ensei Tankado knew it was the last light he would ever see.

  Chapter 1

  They were in the smoky mountains at their favorite bed-and-breakfast. David was smiling down at her. "What do you say, gorgeous? Marry me?"

  Looking up from their canopy bed, she knew he was the one. Forever. As she stared into his deep-green eyes, somewhere in the distance a deafening bell began to ring. It was pulling him away. She reached for him, but her arms clutched empty air.

  It was the sound of the phone that fully awoke Susan Fletcher from her dream. She gasped, sat up in bed, and fumbled for the receiver. "Hello?"

  "Susan, it's David. Did I wake you?"

  She smiled, rolling over in bed. "I was just dreaming of you. Come over and play."

  He laughed. "It's still dark out."

  "Mmm." She moaned sensuously. "Then definitely come over and play. We can sleep in before we head north."

  David let out a frustrated sigh. "That's why I'm calling. It's about our trip. I've got to postpone."

  Susan was suddenly wide awake. "What!"

  "I'm sorry. I've got to leave town. I'll be back by tomorrow. We can head up first thing in the morning. We'll still have two days."

  "But I made reservations," Susan said, hurt. "I got our old room at Stone Manor."

  "I know, but-"

  "Tonight was supposed to be special-to celebrate six months. You do remember we're engaged, don't you?"

  "Susan." He sighed. "I really can't go into it now, they've got a car waiting. I'll call you from the plane and explain everything."

  "Plane?" she repeated. "What's going on? Why would the university…?"

  "It's not the university. I'll phone and explain later. I've really got to go; they're calling for me. I'll be in touch. I promise."

  "David!" she cried. "What's-"

  But it was too late. David had hung up.

  Susan Fletcher lay awake for hours waiting for him to call back. The phone never rang.

  * * *

  Later that afternoon Susan sat dejected in the tub. She submerged herself in the soapy water and tried to forget Stone Manor and the Smoky Mountains. Where could he be? she wondered. Why hasn't he called?

  Gradually the water around her went from hot to lukewarm and finally to cold. She was about to get out when her cordless phone buzzed to life. Susan bolted upright, sloshing water on the floor as she grappled for the receiver she'd left on the sink.

  "David?"

  "It's Strathmore," the voice replied.

  Susan slumped. "Oh." She was unable to hide her disappointment. "Good afternoon, Commander."

  "Hoping for a younger man?" The voice chuckled.

  "No, sir," Susan said, embarrassed. "It's not how it-"

  "Sure it is." He laughed. "David Becker's a good man. Don't ever lose him."

  "Thank you, sir."

  The commander's voice turned suddenly stern. "Susan, I'm calling because I need you in here. Pronto."

  She tried to focus. "It's Saturday, sir. We don't usually-"

  "I know," he said calmly. "It's an emergency."

  Susan sat up. Emergency? She had never heard the word cross Commander Strathmore's lips. An emergency? In Crypto? She couldn't imagine. "Y-yes, sir." She paused. "I'll be there as soon as I can."

  "Make it sooner." Strathmore hung up.

  * * *

  Susan Fletcher stood wrapped in a towel and dripped on the neatly folded clothes she'd set out the night before-hiking shorts, a sweater for the cool mountain evenings, and the new lingerie she'd bought for the nights. Depressed, she went to her closet for a clean blouse and skirt. An emergency? In Crypto?

  As she went downstairs, Susan wondered how the day could get much worse.

  She was about to find out.

  Chapter 2

  Thirty thousand feet above a dead-calm ocean, David Becker stared miserably from the Learjet 60's small, oval window. He'd been told the phone on board was out of order, and he'd never had a chance to call Susan.

  "What am I doing here?" he grumbled to himself. But the answer was simple-there were men to whom you just didn't say no.

  "Mr. Becker," the loudspeaker crackled. "We'll be arriving in half an hour."

  Becker nodded gloomily to the invisible voice. Wonderful. He pulled the shade and tried to sleep. But he could only think of her.

  Chapter 3

  Susan's Volvo sedan rolled to a stop in the shadow of the ten-foot-high, barbed Cyclone fence. A young guard placed his hand on the roof.

  "ID, please."

  Susan obliged and settled in for the usual half-minute wait. The officer ran her card through a computerized scanner. Finally he looked up. "Thank you, Ms. Fletcher." He gave an imperceptible sign, and the gate swung open.

  Half a mile ahead Susan repeated the entire procedure at an equally imposing electrified fence. Come on, guys… I've only been through here a million times.

  As she approached the final checkpoint, a stocky sentry with two attack dogs and a machine gun glanced down at her license plate and waved her through. She followed Canine Road for another 250 yards and pulled into Employee Lot C. Unbelievable, she thought. Twenty-six thousand employees and a twelve-billion-dollar budget; you'd think they could make it through the weekend without me. Susan gunned the car into her reserved spot and killed the engine.

  After crossing the landscaped terrace and entering the main building, she cleared two more internal checkpoints and finally arrived at the windowless tunnel that led to the new wing. A voice-scan booth blocked her entry.

  NATIONAL SECURITY AGENCY (NSA)

  CRYPTO FACILITY

  AUTHORIZED PERSONNEL ONLY

  The armed guard looked up. "Afternoon, Ms. Fletcher."

  Susan smiled tiredly. "Hi, John."

  "Didn't expect you today."

  "Yeah, me neither." She leaned toward the parabolic microphone. "Susan Fletcher," she stated clearly. The computer instantly confirmed the frequency concentrations in her voice, and the gate clicked open. She stepped through.

  * * *

  The guard admired Susan as she began her walk down the cement causeway. He noticed that her strong hazel eyes seemed distant today, but her cheeks had a flushed freshness, and her shoulder-length, auburn hair looked newly blown dry. Trailing her was the faint scent of Johnson's Baby Powder. His eyes fell the length of her slender torso-to her white blouse with the bra barely visible beneath, to her knee-length khaki sk
irt, and finally to her legs… Susan Fletcher's legs.

  Hard to imagine they support a 170 IQ, he mused to himself.

  He stared after her a long time. Finally he shook his head as she disappeared in the distance.

  * * *

  As Susan reached the end of the tunnel, a circular, vaultlike door blocked her way. The enormous letters read: crypto.

  Sighing, she placed her hand inside the recessed cipher box and entered her five-digit PIN. Seconds later the twelve-ton slab of steel began to revolve. She tried to focus, but her thoughts reeled back to him.

  David Becker. The only man she'd ever loved. The youngest full professor at Georgetown University and a brilliant foreign-language specialist, he was practically a celebrity in the world of academia. Born with an eidetic memory and a love of languages, he'd mastered six Asian dialects as well as Spanish, French, and Italian. His university lectures on etymology and linguistics were standing-room only, and he invariably stayed late to answer a barrage of questions. He spoke with authority and enthusiasm, apparently oblivious to the adoring gazes of his star-struck coeds.

  Becker was dark-a rugged, youthful thirty-five with sharp green eyes and a wit to match. His strong jaw and taut features reminded Susan of carved marble. Over six feet tall, Becker moved across a squash court faster than any of his colleagues could comprehend. After soundly beating his opponent, he would cool off by dousing his head in a drinking fountain and soaking his tuft of thick, black hair. Then, still dripping, he'd treat his opponent to a fruit shake and a bagel.

  As with all young professors, David's university salary was modest. From time to time, when he needed to renew his squash club membership or restring his old Dunlop with gut, he earned extra money by doing translating work for government agencies in and around Washington. It was on one of those jobs that he'd met Susan.

  It was a crisp morning during fall break when Becker returned from a morning jog to his three-room faculty apartment to find his answering machine blinking. He downed a quart of orange juice as he listened to the playback. The message was like many he received-a government agency requesting his translating services for a few hours later that morning. The only strange thing was that Becker had never heard of the organization.

  "They're called the National Security Agency," Becker said, calling a few of his colleagues for background.

  The reply was always the same. "You mean the National Security Council?"

  Becker checked the message. "No. They said Agency. The NSA."

  "Never heard of 'em."

  Becker checked the GAO Directory, and it showed no listing either. Puzzled, Becker called one of his old squash buddies, an ex-political analyst turned research clerk at the Library of Congress. David was shocked by his friend's explanation.

  Apparently, not only did the NSA exist, but it was considered one of the most influential government organizations in the world. It had been gathering global electronic intelligence data and protecting U.S. classified information for over half a century. Only 3 percent of Americans were even aware it existed.

  "NSA," his buddy joked, "stands for 'No Such Agency.' "

  With a mixture of apprehension and curiosity, Becker accepted the mysterious agency's offer. He drove the thirty-seven miles to their eighty-six-acre headquarters hidden discreetly in the wooded hills of Fort Meade, Maryland. After passing through endless security checks and being issued a six-hour, holographic guest pass, he was escorted to a plush research facility where he was told he would spend the afternoon providing "blind support" to the Cryptography Division-an elite group of mathematical brainiacs known as the code-breakers.

  For the first hour, the cryptographers seemed unaware Becker was even there. They hovered around an enormous table and spoke a language Becker had never heard. They spoke of stream ciphers, self-decimated generators, knapsack variants, zero knowledge protocols, unicity points. Becker observed, lost. They scrawled symbols on graph paper, pored over computer printouts, and continuously referred to the jumble of text on the overhead projector.

  JHdja3jKHDhmado/ertwtjlw+jgj328 5jhalsfnHKhhhfafOhhdfgaf/fj37we ohi93450s9djfd2h/HHrtyFHLf89303 95jspjf2j0890Ihj98yhfi080ewrt03 jojr845h0roq+jt0eu4tqefqe//oujw 08UY0IH0934jtpwfiajer09qu4jr9gu ivjP$duw4h95pe8rtugvjw3p4e/ikkc mffuerhfgv0q394ikjrmg+unhvs9oer rk/0956y7u0poikIOjp9f8760qwerqi Eventually one of them explained what Becker had already surmised. The scrambled text was a code-a "cipher text"-groups of numbers and letters representing encrypted words. The cryptographers' job was to study the code and extract from it the original message, or "cleartext." The NSA had called Becker because they suspected the original message was written in Mandarin Chinese; he was to translate the symbols as the cryptographers decrypted them.

  For two hours, Becker interpreted an endless stream of Mandarin symbols. But each time he gave them a translation, the cryptographers shook their heads in despair. Apparently the code was not making sense. Eager to help, Becker pointed out that all the characters they'd shown him had a common trait-they were also part of the Kanji language. Instantly the bustle in the room fell silent. The man in charge, a lanky chain-smoker named Morante, turned to Becker in disbelief.

  "You mean these symbols have multiple meanings?"

  Becker nodded. He explained that Kanji was a Japanese writing system based on modified Chinese characters. He'd been giving Mandarin translations because that's what they'd asked for.

  "Jesus Christ." Morante coughed. "Let's try the Kanji."

  Like magic, everything fell into place.

  The cryptographers were duly impressed, but nonetheless, they still made Becker work on the characters out of sequence. "It's for your own safety," Morante said. "This way, you won't know what you're translating."

  Becker laughed. Then he noticed nobody else was laughing.

  When the code finally broke, Becker had no idea what dark secrets he'd helped reveal, but one thing was for certain-the NSA took code-breaking seriously; the check in Becker's pocket was more than an entire month's university salary.

  On his way back out through the series of security check points in the main corridor, Becker's exit was blocked by a guard hanging up a phone. "Mr. Becker, wait here, please."

  "What's the problem?" Becker had not expected the meeting to take so long, and he was running late for his standing Saturday afternoon squash match.

  The guard shrugged. "Head of Crypto wants a word. She's on her way out now."

  "She?" Becker laughed. He had yet to see a female inside the NSA.

  "Is that a problem for you?" a woman's voice asked from behind him.

  Becker turned and immediately felt himself flush. He eyed the ID card on the woman's blouse. The head of the NSA's Cryptography Division was not only a woman, but an attractive woman at that.

  "No," Becker fumbled. "I just…"

  "Susan Fletcher." The woman smiled, holding out her slender hand.

  Becker took it. "David Becker."

  "Congratulations, Mr. Becker. I hear you did a fine job today. Might I chat with you about it?"

  Becker hesitated. "Actually, I'm in a bit of a rush at the moment." He hoped spurning the world's most powerful intelligence agency wasn't a foolish act, but his squash match started in forty-five minutes, and he had a reputation to uphold: David Becker was never late for squash… class maybe, but never squash.

  "I'll be brief." Susan Fletcher smiled. "Right this way, please."

  Ten minutes later, Becker was in the NSA's commissary enjoying a popover and cranberry juice with the NSA's lovely head cryptographer, Susan Fletcher. It quickly became evident to David that the thirty-eight-year-old's high-ranking position at the NSA was no fluke-she was one of the brightest women he had ever met. As they discussed codes and code-breaking, Becker found himself struggling to keep up-a new and exciting experience for him.

  An hour later, after Becker had obviously missed his squash match and Susan had blatantly ignored three pages on the intercom, both of them had to laugh. There they were, two highly ana
lytical minds, presumably immune to irrational infatuations-but somehow, while they sat there discussing linguistic morphology and pseudo-random number generators, they felt like a couple of teenagers-everything was fireworks.

  Susan never did get around to the real reason she'd wanted to speak to David Becker-to offer him a trial post in their Asiatic Cryptography Division. It was clear from the passion with which the young professor spoke about teaching that he would never leave the university. Susan decided not to ruin the mood by talking business. She felt like a schoolgirl all over again; nothing was going to spoil it. And nothing did.

  * * *

  Their courtship was slow and romantic-stolen escapes whenever their schedules permitted, long walks through the Georgetown campus, late-night cappuccinos at Merlutti's, occasional lectures and concerts. Susan found herself laughing more than she'd ever thought possible. It seemed there was nothing David couldn't twist into a joke. It was a welcome release from the intensity of her post at the NSA.

  One crisp, autumn afternoon they sat in the bleachers watching Georgetown soccer get pummeled by Rutgers.

  "What sport did you say you play?" Susan teased. "Zucchini?"

  Becker groaned. "It's called squash."

  She gave him a dumb look.

  "It's like zucchini," he explained, "but the court's smaller."

  Susan pushed him.

  Georgetown's left wing sent a corner-kick sailing out of bounds, and a boo went up from the crowd. The defensemen hurried back downfield.