The Mona Lisa. For an instant, standing in the exit stairwell, Sophie forgot all about trying to leave the Louvre. Her shock over the anagram was matched only by her embarrassment at not having deciphered the message herself. Sophie's expertise in complex cryptanalysis had caused her to overlook simplistic word games, and yet she knew she should have seen it. After all, she was no stranger to anagrams -- especially in English.

When she was young, often her grandfather would use anagram games to hone her English spelling. Once he had written the English word "planets" and told Sophie that an astonishing sixty-two other English words of varying lengths could be formed using those same letters. Sophie had spent three days with an English dictionary until she found them all.

"I can't imagine," Langdon said, staring at the printout, "how your grandfather created such an intricate anagram in the minutes before he died."Sophie knew the explanation, and the realization made her feel even worse. I should have seen this! She now recalled that her grandfather -- a wordplay aficionado and art lover -- had entertained himself as a young man by creating anagrams of famous works of art. In fact, one of his anagrams had gotten him in trouble once when Sophie was a little girl. While being interviewed by an American art magazine, Sauniere had expressed his distaste for the modernist Cubist movement by noting that Picasso's masterpiece Les Demoiselles d'Avignon was a perfect anagram of vile meaningless doodles. Picasso fans were not amused.

"My grandfather probably created this Mona Lisa anagram long ago," Sophie said, glancing up at Langdon. And tonight he was forced to use it as a makeshift code. Her grandfather's voice had called out from beyond with chilling precision. Leonardo da Vinci! The Mona Lisa!

Why his final words to her referenced the famous painting, Sophie had no idea, but she could think of only one possibility. A disturbing one. Those were not his final words… Was she supposed to visit the Mona Lisa? Had her grandfather left her a message there? The idea seemed perfectly plausible. After all, the famous painting hung in the Salle des Etats -- a private viewing chamber accessible only from the Grand Gallery. In fact, Sophie now realized, the doors that opened into the chamber were situated only twenty meters from where her grandfather had been found dead. He easily could have visited the Mona Lisa before he died. Sophie gazed back up the emergency stairwell and felt torn. She knew she should usher Langdon from the museum immediately, and yet instinct urged her to the contrary. As Sophie recalled her first childhood visit to the Denon Wing, she realized that if her grandfather had a secret to tell her, few places on earth made a more apt rendezvous than Da Vinci's Mona Lisa.

"She's just a little bit farther," her grandfather had whispered, clutching Sophie's tiny hand as he led her through the deserted museum after hours. Sophie was six years old. She felt small and insignificant as she gazed up at the enormous ceilings and down at the dizzying floor. The empty museum frightened her, although she was not about to let her grandfather know that. She set her jaw firmly and let go of his hand.

"Up ahead is the Salle des Etats," her grandfather said as they approached the Louvre's most famous room. Despite her grandfather's obvious excitement, Sophie wanted to go home. She had seen pictures of the Mona Lisa in books and didn't like it at all. She couldn't understand why everyone made such a fuss.

"C'est ennuyeux," Sophie grumbled. "Boring," he corrected. "French at school. English at home."

"Le Louvre, c'est pas chez moi!" she challenged. He gave her a tired laugh. "Right you are. Then let's speak English just for fun."

Sophie pouted and kept walking. As they entered the Salle des Etats, her eyes scanned the narrow room and settled on the obvious spot of honor -- the center of the right-hand wall, where a lone portrait hung behind a protective Plexiglas wall. Her grandfather paused in the doorway and motioned toward the painting."Go ahead, Sophie. Not many people get a chance to visit her alone."

"She's too little." Sauniere smiled. "You're little and you're beautiful." I am not beautiful, she thought. Sophie hated her red hair and freckles, and she was bigger than all the boys in her class. She looked back at the Mona Lisa and shook her head. "She's even worse than in the books. Her face is… brumeux."

"Foggy," her grandfather tutored. "Foggy," Sophie repeated, knowing the conversation would not continue until she repeated her new vocabulary word. "That's called the sfumato style of painting," he told her, "and it's very hard to do. Leonardo da Vinci was better at it than anyone."

Swallowing her apprehension, Sophie moved slowly across the room. After everything she'd heard about the Mona Lisa, she felt as if she were approaching royalty. Arriving in front of the protective Plexiglas, Sophie held her breath and looked up, taking it in all at once. Sophie was not sure what she had expected to feel, but it most certainly was not this. No jolt of amazement. No instant of wonder. The famous face looked as it did in books. She stood in silence for what felt like forever, waiting for something to happen.

"So what do you think?" her grandfather whispered, arriving behind her. "Beautiful, yes?"

"Do you know why she's smiling?"

"Maybe." Her grandfather winked. "Someday I'll tell you all about it." Sophie stamped her foot. "I told you I don't like secrets!"

"Princess," he smiled. "Life is filled with secrets. You can't learn them all at once."

"What about the embassy?"

Sophie still didn't like the painting. "She looks like she knows something… like when kids at school have a secret." Her grandfather laughed. "That's part of why she is so famous. People like to guess why she is smiling."

Sophie felt guilty turning Langdon into a fugitive only to abandon him, but she saw no other option. She pointed down the stairs to a metal door. "Go through that door, and follow the illuminated exit signs. My grandfather used to bring me down here. The signs will lead you to a security turnstile. It's mono-directional and opens out." She handed Langdon her car keys. "Mine is the red SmartCar in the employee lot. Directly outside this bulkhead. Do you know how to get to the embassy?" Langdon nodded, eyeing the keys in his hand.

"I'm going back up," Sophie declared, her voice hollow in the stairwell. "To the Mona Lisa?" Langdon recoiled. "Now?" Sophie considered the risk. "I'm not a murder suspect. I'll take my chances. I need to understand what my grandfather was trying to tell me."

"Listen," Sophie said, her voice softening. "I think my grandfather may have left me a message at the Mona Lisa -- some kind of clue as to who killed him. Or why I'm in danger. Or what happened to my family."

"But if he wanted to tell you why you were in danger, why wouldn't he simply write it on the floor where he died? Why this complicated word game?"

"Whatever my grandfather was trying to tell me, I don't think he wanted anyone else to hear it. Not even the police." Clearly, her grandfather had done everything in his power to send a confidential transmission directly to her. He had written it in code, included her secret initials, and told her to find Robert Langdon -- a wise command, considering the American symbologist had deciphered his code.

"As strange as it may sound," Sophie said, "I think he wants me to get to the Mona Lisa before anyone else does."

"I have to go see."

"I'll come."

"No! We don't know how long the Grand Gallery will stay empty. You have to go." Langdon seemed hesitant, as if his own academic curiosity were threatening to override sound judgment and drag him back into Fache's hands. "Go. Now." Sophie gave him a grateful smile. "I'll see you at the embassy, Mr. Langdon." Langdon looked displeased. "I'll meet you there on one condition," he replied, his voice stern. She paused, startled. "What's that?"

When Langdon reached the landing at the bottom of the stairs, the unmistakable smell of linseed oil and plaster dust assaulted his nostrils. Ahead, an illuminated SORTIE/EXIT displayed an arrow pointing down a long corridor. Langdon stepped into the hallway. To the right gaped a murky restoration studio out of which peered an army of statues in various states of repair. To the left, Langdon saw a suite of studios that resembled Harvard art classrooms -- rows of easels, paintings, palettes, framing tools -- an art assembly line. As he moved down the hallway, Langdon wondered if at any moment he might awake with a start in his bed in Cambridge. The entire evening had felt like a bizarre dream. I'm about to dash out of the Louvre… a fugitive.

"That you stop calling me Mr. Langdon." Sophie detected the faint hint of a lopsided grin growing across Langdon's face, and she felt herself smile back. "Good luck, Robert."

Sauniere's clever anagrammatic message was still on his mind, and Langdon wondered what Sophie would find at the Mona Lisa… if anything. She had seemed certain her grandfather meant for her to visit the famous painting one more time. As plausible an interpretation as this seemed, Langdon felt haunted now by a troubling paradox. P. S. Find Robert Langdon. Sauniere had written Langdon's name on the floor, commanding Sophie to find him. But why? Merely so Langdon could help her break an anagram?

With an unexpected jolt, Langdon stopped short. Eyes wide, he dug in his pocket and yanked out the computer printout. He stared at the last line of Sauniere's message. P. S. Find Robert Langdon. He fixated on two letters. P. S. In that instant, Langdon felt Sauniere's puzzling mix of symbolism fall into stark focus. Like a peal of thunder, a career's worth of symbology and history came crashing down around him. Everything Jacques Sauniere had done tonight suddenly made perfect sense.

Langdon's thoughts raced as he tried to assemble the implications of what this all meant. Wheeling, he stared back in the direction from which he had come. Is there time? He knew it didn't matter. Without hesitation, Langdon broke into a sprint back toward the stairs.

It seemed quite unlikely. After all, Sauniere had no reason to think Langdon was especially skilled at anagrams. We've never even met. More important, Sophie had stated flat out that she should have broken the anagram on her own. It had been Sophie who spotted the Fibonacci sequence, and, no doubt, Sophie who, if given a little more time, would have deciphered the message with no help from Langdon. Sophie was supposed to break that anagram on her own. Langdon was suddenly feeling more certain about this, and yet the conclusion left an obvious gaping lapse in the logic of Sauniere's actions. Why me? Langdon wondered, heading down the hall. Why was Sauniere's dying wish that his estranged granddaughter find me? What is it that Sauniere thinks I know?