André Vernet -- president of the Paris branch of the Depository Bank of Zurich -- lived in a lavish flat above the bank. Despite his plush accommodations, he had always dreamed of owning a riverside apartment on L'lle Saint-Louis, where he could rub shoulders with the true cognoscenti, rather than here, where he simply met the filthy rich.

Tonight, Vernet had been awake only six and a half minutes. Even so, as he hurried through the bank's underground corridor, he looked as if his personal tailor and hairdresser had polished him to a fine sheen. Impeccably dressed in a silk suit, Vernet sprayed some breath spray in his mouth and tightened his tie as he walked. No stranger to being awoken to attend to his international clients arriving from different time zones, Vernet modeled his sleep habits after the Maasai warriors -- the African tribe famous for their ability to rise from the deepest sleep to a state of total battle readiness in a matter of seconds.

When I retire, Vernet told himself, I will fill my cellar with rare Bordeaux, adorn my salon with a Fragonard and perhaps a Boucher, and spend my days hunting for antique furniture and rare books in the Quartier Latin.

Five minutes, Vernet told himself. I need these people out of my bank before the police arrive.

Battle ready, Vernet thought, fearing the comparison might be uncharacteristically apt tonight. The arrival of a gold key client always required an extra flurry of attention, but the arrival of a gold key client who was wanted by the Judicial Police would be an extremely delicate matter. The bank had enough battles with law enforcement over the privacy rights of their clients without proof that some of them were criminals.

If he moved quickly, this impending disaster could be deftly sidestepped. Vernet could tell the police that the fugitives in question had indeed walked into his bank as reported, but because they were not clients and had no account number, they were turned away. He wished the damned watchman had not called Interpol. Discretion was apparently not part of the vocabulary of a 15-euro-per-hour watchman.

Stopping at the doorway, he took a deep breath and loosened his muscles. Then, forcing a balmy smile, he unlocked the door and swirled into the room like a warm breeze.

"My grandfather gave it to me," Sophie replied, watching the man closely. His uneasiness seemed more evident now.

"Good evening," he said, his eyes finding his clients. "I am André Vernet. How can I be of serv --" The rest of the sentence lodged somewhere beneath his Adam's apple. The woman before him was as unexpected a visitor as Vernet had ever had.

"No…," the bank president fumbled. "I don't… believe so. Our services are anonymous." He exhaled and forced a calm smile. "My assistant tells me you have a gold key but no account number? Might I ask how you came by this key?"

"I'm sorry, do we know each other?" Sophie asked. She did not recognize the banker, but he for a moment looked as if he'd seen a ghost.

"Really? Your grandfather gave you the key but failed to give you the account number?"

"I don't think he had time," Sophie said. "He was murdered tonight."

Her words sent the man staggering backward. "Jacques Saunière is dead?" he demanded, his eyes filling with horror. "But… how?!"

Now it was Sophie who reeled, numb with shock. "You knew my grandfather?"

Banker André Vernet looked equally astounded, steadying himself by leaning on an end table. "Jacques and I were dear friends. When did this happen?"

"Earlier this evening. Inside the Louvre."

Vernet walked to a deep leather chair and sank into it. "I need to ask you both a very important question." He glanced up at Langdon and then back to Sophie. "Did either of you have anything to do with his death?"

Sophie slumped. Fache ran an Interpol broadcast already? It seemed the captain was more motivated than Sophie had anticipated. She quickly told Vernet who Langdon was and what had happened inside the Louvre tonight.

"Yes. And this key." Sophie laid the gold key on the coffee table in front of Vernet, placing the Priory seal face down.

"No!" Sophie declared. "Absolutely not."

Vernet looked amazed. "And as your grandfather was dying, he left you a message telling you to find Mr. Langdon?"

Vernet's face was grim, and he paused, pondering. "Your pictures are being circulated by Interpol. This is how I recognized you. You're wanted for a murder."

Vernet gave a helpless sigh. "I'm afraid every key is electronically paired with a ten-digit account number that functions as a password. Without that number, your key is worthless." Ten digits. Sophie reluctantly calculated the cryptographic odds. Over ten billion possible choices.

Vernet glanced at the key but made no move to touch it. "He left you only this key? Nothing else? No slip of paper?"

"No. Just the key."

Sophie knew she had been in a hurry inside the Louvre, but she was certain she had seen nothing else behind Madonna of the Rocks.

Even if she could bring in DCPJ's most powerful parallel processing computers, she still would need weeks to break the code. "Certainly, monsieur, considering the circumstances, you can help us."

"I'm sorry. I truly can do nothing. Clients select their own account numbers via a secure terminal, meaning account numbers are known only to the client and computer. This is one way we ensure anonymity. And the safety of our employees." Sophie understood. Convenience stores did the same thing. EMPLOYEES DO NOT HAVE KEYSTO THE SAFE. This bank obviously did not want to risk someone stealing a key and then holding an employee hostage for the account number.

"Monsieur Vernet," she pressed, "our time tonight is short. I am going to be very direct if I may." She reached out to the gold key and flipped it over, watching the man's eyes as she revealed the Priory of Sion seal. "Does the symbol on this key mean anything to you?"

Sophie sat down beside Langdon, glanced down at the key and then up at Vernet. "Do you have any idea what my grandfather is storing in your bank?"

"None whatsoever. That is the definition of a Geldschrank bank."

Vernet glanced down at the fleur-de-lis seal and made no reaction. "No, but many of our clients emboss corporate logos or initials onto their keys." Sophie sighed, still watching him carefully. "This seal is the symbol of a secret society known as the Priory of Sion." Vernet again showed no reaction. "I know nothing of this. Your grandfather was a friend, but we spoke mostly of business." The man adjusted his tie, looking nervous now.

"Monsieur Vernet," Sophie pressed, her tone firm. "My grandfather called me tonight and told me he and I were in grave danger. He said he had to give me something. He gave me a key to your bank. Now he is dead. Anything you can tell us would be helpful." Vernet broke a sweat. "We need to get out of the building. I'm afraid the police will arrive shortly. My watchman felt obliged to call Interpol." Sophie had feared as much. She took one last shot. "My grandfather said he needed to tell me the truth about my family. Does that mean anything to you?"

Hanging up the phone, he turned back to Sophie. "The police have responded far more quickly than usual. They are arriving as we speak." Sophie had no intention of leaving empty-handed. "Tell them we came and went already. If they want to search the bank, demand a search warrant. That will take them time."

Langdon asked, "Do the contents of this account have anything to do with the Sangreal?"

"Mademoiselle, your family died in a car accident when you were young. I'm sorry. I know your grandfather loved you very much. He mentioned to me several times how much it pained him that you two had fallen out of touch." Sophie was uncertain how to respond.

Vernet gave him an odd look. "I have no idea what that is." Just then, Vernet's cell phone rang, and he snatched it off his belt. "Oui?" He listened a moment, his expression one of surprise and growing concern. "La police? Si rapidement?" He cursed, gave some quick directions in French, and said he would be up to the lobby in a minute.

"Listen," Vernet said, "Jacques was a friend, and my bank does not need this kind of press, so for those two reasons, I have no intention of allowing this arrest to be made on my premises. Give me a minute and I will see what I can do to help you leave the bank undetected. Beyond that, I cannot get involved." He stood up and hurried for the door. "Stay here. I'll make arrangements and be right back."

Langdon stood suddenly, and Sophie sensed an unexpected glimmer of contentment in his eyes.

"Robert? You're smiling."

Sophie had no idea what he was talking about.

"Your grandfather was a genius."

Oh, lame saint!

"I'm sorry?"

"Where?"

"The account number," he said, a familiar lopsided grin now craning his face. "I'm pretty sure he left it for us after all."

"But the safe-deposit box," Sophie declared. "We can't just leave."

Langdon produced the printout of the crime scene photo and spread it out on the coffee table.

"Ten digits?"

Sophie needed only to read the first line to know Langdon was correct.

"There's nothing I can do," Vernet said, hurrying out the door. "I'm sorry."

13-3-2-21-1-1-8-5O, Draconian devil!

P. S. Find Robert Langdon

Sophie stared after him a moment, wondering if maybe the account number was buried in one of the countless letters and packages her grandfather had sent her over the years and which she had left unopened.