Langdon still felt shaky as he and Sophie came in from the rain and entered the library. The primary research room was as Teabing had described it-a dramatic octagonal chamber dominated by an enormous round table around which King Arthur and his knights might have been comfortable were it not for the presence of twelve flat-screen computer workstations. On the far side of the room, a reference librarian was just pouring a pot of tea and settling in for her day of work.

King's College, established by King George IV in 1829, houses its Department of Theology and Religious Studies adjacent to Parliament on property granted by the Crown. King's College Religion Department boasts not only 150 years' experience in teaching and research, but the 1982 establishment of the Research Institute in Systematic Theology, which possesses one of the most complete and electronically advanced religious research libraries in the world.

"Lovely morning," she said in a cheerful British accent, leaving the tea and walking over. "May I help you?"

The two women greeted one another, and Gettum turned immediately back to Langdon. "I didn't know you were coming."

For an instant, he feared Fache had put him on English television as well, but the librarian's smile suggested otherwise. Langdon still had not gotten used to these moments of unexpected celebrity. Then again, if anyone on earth were going to recognize his face, it would be a librarian in a Religious Studies reference facility.

"Thank you, yes," Langdon replied. "My name is-"

"Robert Langdon." She gave a pleasant smile. "I know who you are."

Gettum shifted, looking uncertain. "Normally our services are by petition and appointment only, unless of course you're the guest of someone at the college?"

"Pamela Gettum," the librarian said, offering her hand. She had a genial, erudite face and a pleasingly fluid voice. The horn-rimmed glasses hanging around her neck were thick.

"Neither did we. If it's not too much trouble, we could really use your help finding some information."

"A pleasure," Langdon said. "This is my friend Sophie Neveu."

Langdon shook his head. "I'm afraid we've come unannounced. A friend of mine speaks very highly of you. Sir Leigh Teabing?" Langdon felt a pang of gloom as he said the name. "The British Royal Historian."

"Is there any chance you can help us?" Sophie asked. "It's quite important."

Gettum brightened now, laughing. "Heavens, yes. What a character. Fanatical! Every time he comes in, it's always the same search strings. Grail. Grail. Grail. I swear that man will die before he gives up on that quest." She winked. "Time and money afford one such lovely luxuries, wouldn't you say? A regular Don Quixote, that one."

"We're trying to find a tomb in London."

Gettum looked dubious. "We've got about twenty thousand of them. Can you be a little more specific?"

Gettum glanced around the deserted library and then winked at them both. "Well, I can't very well claim I'm too busy, now can I? As long as you sign in, I can't imagine anyone being too upset. What did you have in mind?"

"It's the tomb of a knight. We don't have a name."

"We don't have much information about the knight we're looking for," Sophie said, "but this is what we know." She produced a slip of paper on which she had written only the first two lines of the poem.

"A knight. That tightens the net substantially. Much less common."

In this case, the precaution was probably excessive; even if this librarian saw the entire poem, identified the knight's tomb, and knew what orb was missing, the information was useless without the cryptex.

Gettum sensed an urgency in the eyes of this famed American scholar, almost as if his finding this tomb quickly were a matter of critical importance. The green-eyed woman accompanying him also seemed anxious.

Hesitant to show the entire poem to an outsider, Langdon and Sophie had decided to share just the first two lines, those that identified the knight. Compartmentalized cryptography, Sophie had called it. When an intelligence agency intercepted a code containing sensitive data, cryptographers each worked on a discrete section of the code. This way, when they broke it, no single cryptographer possessed the entire deciphered message.

Gettum moved toward one of the workstations. "Not offhand, but let's see what we can pull up in the database."

His labor's fruit a Holy wrath incurred.

In London lies a knight a Pope interred.

She glanced at her guests. "What is this? Some kind of Harvard scavenger hunt?"

Puzzled, Gettum put on her glasses and examined the paper they had just handed her.

Langdon's laugh sounded forced. "Yeah, something like that."

Over the past two decades, King's College Research Institute in Systematic Theology had used optical character recognition software in unison with linguistic translation devices to digitize and catalog an enormous collection of texts-encyclopedias of religion, religious biographies, sacred scriptures in dozens of languages, histories, Vatican letters, diaries of clerics, anything at all that qualified as writings on human spirituality. Because the massive collection was now in the form of bits and bytes rather than physical pages, the data was infinitely more accessible.

Gettum paused, feeling she was not getting the whole story. Nonetheless, she felt intrigued and found herself pondering the verse carefully. "According to this rhyme, a knight did something that incurred displeasure with God, and yet a Pope was kind enough to bury him in London."

Langdon nodded. "Does it ring any bells?"

Gettum shook her head. "Obviously not what you're looking for."

She scrolled to the next hit.

Painting the Pope. The Collected Portraits of Sir Joshua Reynolds. London University Press.

The screen was already showing the first of the hits now.

"Thank you."

LONDON, KNIGHT, POPE

As the system churned on, the hits came up more quickly than usual. Dozens of texts appeared, many of them referencing the eighteenth-century British writer Alexander Pope, whose counterreligious, mock-epic poetry apparently contained plenty of references to knights and London.

Gettum typed in a few words:

The London Writings of Alexander Pope by G. Wilson Knight.

Again she shook her head.

Settling into one of the workstations, Gettum eyed the slip of paper and began typing. "To begin, we'll run a straight Boolean with a few obvious keywords and see what happens."

As she clicked the SEARCH button, she could feel the hum of the massive mainframe downstairs scanning data at a rate of 500 MB/sec. "I'm asking the system to show us any documents whose complete text contains all three of these keywords. We'll get more hits than we want, but it's a good place to start."

Gettum shot a quick glance to the numeric field at the bottom of the screen. This computer, by calculating the current number of hits and multiplying by the percentage of the database left to search, provided a rough guess of how much information would be found. This particular search looked like it was going to return an obscenely large amount of data.

Estimated number of total hits: 2,692

This is no scavenger hunt, Gettum sensed. She had heard the whisperings of Robert Langdon's experience in Rome last year. This American had been granted access to the most secure library on earth-the Vatican Secret Archives. She wondered what kinds of secrets Langdon might have learned inside and if his current desperate hunt for a mysterious London tomb might relate to information he had gained within the Vatican. Gettum had been a librarian long enough to know the most common reason people came to London to look for knights. The Grail.

"We need to refine the parameters further," Gettum said, stopping the search. "Is this all the information you have regarding the tomb? There's nothing else to go on?"

Langdon glanced at Sophie Neveu, looking uncertain.

Langdon and Sophie exchanged startled looks.

Gettum smiled and adjusted her glasses. "You are friends with Leigh Teabing, you are in England, and you are looking for a knight." She folded her hands. "I can only assume you are on a Grail quest."

Gettum laughed. "My friends, this library is a base camp for Grail seekers. Leigh Teabing among them. I wish I had a shilling for every time I'd run searches for the Rose, Mary Magdalene, Sangreal, Merovingian, Priory of Sion, et cetera, et cetera. Everyone loves a conspiracy." She took off her glasses and eyed them. "I need more information."

In the silence, Gettum sensed her guests' desire for discretion was quickly being outweighed by their eagerness for a fast result.

You seek the orb that ought be on his tomb.

It speaks of Rosy flesh and seeded womb.

Gettum gave an inward smile. The Grail indeed, she thought, noting the references to the Rose and her seeded womb. "I can help you," she said, looking up from the slip of paper. "Might I ask where this verse came from? And why you are seeking an orb?"

"Here," Sophie Neveu blurted. "This is everything we know." Borrowing a pen from Langdon, she wrote two more lines on the slip of paper and handed it to Gettum.

"Sounds like a polite way of saying 'mind your own business.'"

"We would be forever in your debt, Pamela," Langdon said, "if you could find out who this knight is and where he is buried."

"You might ask," Langdon said, with a friendly smile, "but it's a long story and we have very little time."

"Very well," Gettum said, typing again. "I'll play along. If this is a Grail-related issue, we should cross-reference against Grail keywords. I'll add a proximity parameter and remove the title weighting. That will limit our hits only to those instances of textual keywords that occur near a Grail-related word."

Search for: KNIGHT, LONDON, POPE, TOMB

"A few hundred terabytes with multiple cross-referencing fields?" Gettum's eyes glimmered as she clicked the SEARCH key. "A mere fifteen minutes."

"How long will this take?" Sophie asked.

Langdon and Sophie said nothing, but Gettum sensed this sounded like an eternity to them.

Within 100 word proximity of: GRAIL, ROSE, SANGREAL, CHALICE

"Tea?" Gettum asked, standing and walking toward the pot she had made earlier. "Leigh always loves my tea."