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.
For my parents… my mentors and heroes
A debt of gratitude: to my editors at St. Martin's Press, Thomas Dunne and the exceptionally talented Melissa Jacobs. To my agents in New York, George Wieser, Olga Wieser, and Jake Elwell. To all those who read and contributed to the manuscript along the way. And especially to my wife, Blythe, for her enthusiasm and patience.
Also… a quiet thank you to the two faceless ex-NSA cryptographers who made invaluable contributions via anonymous remailers. Without them this book would not have been written.
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.
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.
