Robert Langdon’s claustrophobia gripped him more tightly with every hastening step of their descent. As they moved deeper into the building’s original foundation, the air became heavy, and the ventilation seemed nonexistent. The walls down here were an uneven blend of stone and yellow brick.

Director Sato typed on her BlackBerry as they walked. Langdon sensed a suspicion in her guarded manner, but the feeling was quickly becoming reciprocal. Sato still hadn’t told him how she knew Langdon was here tonight. An issue of national security? He had a hard time understanding any relation between ancient mysticism and national security. Then again, he had a hard time understanding much of anything about this situation.

Peter Solomon entrusted me with a talisman . . . a deluded lunatic tricked me into bringing it to the Capitol and wants me to use it to unlock a mystical portal . . . possibly in a room called SBB13.

Not exactly a clear picture.

As they pressed on, Langdon tried to shake from his mind the horrible image of Peter’s tattooed hand, transformed into the Hand of the Mysteries. The gruesome picture was accompanied by Peter’s voice: The Ancient Mysteries, Robert, have spawned many myths . . . but that does not mean they themselves are fiction.

Despite a career studying mystical symbols and history, Langdon had always struggled intellectually with the idea of the Ancient Mysteries and their potent promise of apotheosis.

Admittedly, the historical record contained indisputable evidence that secret wisdom had been passed down through the ages, apparently having come out of the Mystery Schools in early Egypt. This knowledge moved underground, resurfacing in Renaissance Europe, where, according to most accounts, it was entrusted to an elite group of scientists within the walls of Europe’s premier scientific think tank—the Royal Society of London—enigmatically nicknamed the Invisible College.

This concealed “college” quickly became a brain trust of the world’s most enlightened minds—those of Isaac Newton, Francis Bacon, Robert Boyle, and even Benjamin Franklin. Today, the list of modern “fellows” was no less impressive—Einstein, Hawking, Bohr, and Celsius. These great minds had all made quantum leaps in human understanding, advances that, according to some, were the result of their exposure to ancient wisdom hidden within the Invisible College. Langdon doubted this was true, although certainly there had been an unusual amount of “mystical work” taking place within those walls.

The discovery of Isaac Newton’s secret papers in 1936 had stunned the world by revealing Newton’s all-consuming passion for the study of ancient alchemy and mystical wisdom. Newton’s private papers included a handwritten letter to Robert Boyle in which he exhorted Boyle to keep “high silence” regarding the mystical knowledge they had learned. “It cannot be communicated,” Newton wrote, “without immense damage to the world.”

The meaning of this strange warning was still being debated today.

“Professor,” Sato said suddenly, glancing up from her BlackBerry, “despite your insistence that you have no idea why you’re here tonight, perhaps you could shed light on the meaning of Peter Solomon’s ring.”

“I can try,” Langdon said, refocusing.

She produced the specimen bag and handed it to Langdon. “Tell me about the symbols on his ring.”

Langdon examined the familiar ring as they moved through the deserted passageway. Its face bore the image of a double-headed phoenix holding a banner proclaiming ORDO AB CHAO, and its chest was emblazoned with the number 33. “The double-headed phoenix with the number thirty-three is the emblem of the highest Masonic degree.” Technically, this prestigious degree existed solely within the Scottish Rite. Nonetheless, the rites and degrees of Masonry were a complex hierarchy that Langdon had no desire to detail for Sato tonight. “Essentially, the thirty-third degree is an elite honor reserved for a small group of highly accomplished Masons. All the other degrees can be attained by successful completion of the previous degree, but ascension to the thirty-third degree is controlled. It’s by invitation only.”

“So you were aware that Peter Solomon was a member of this elite inner circle?”

“Of course. Membership is hardly a secret.”

“And he is their highest-ranking official?”

“Currently, yes. Peter heads the Supreme Council Thirty-third Degree, which is the governing body of the Scottish Rite in America.” Langdon always loved visiting their headquarters—the House of the Temple—a classical masterpiece whose symbolic ornamentation rivaled that of Scotland’s Rosslyn Chapel.

“Professor, did you notice the engraving on the ring’s band? It bears the words ‘All is revealed at the thirty-third degree.’ ”

Langdon nodded. “It’s a common theme in Masonic lore.”

“Meaning, I assume, that if a Mason is admitted to this highest thirty-third degree, then something special is revealed to him?”

“Yes, that’s the lore, but probably not the reality. There’s always been conspiratorial conjecture that a select few within this highest echelon of Masonry are made privy to some great mystical secret. The truth, I suspect, is probably far less dramatic.”

Peter Solomon often made playful allusions to the existence of a precious Masonic secret, but Langdon always assumed it was just a mischievous attempt to coax him into joining the brotherhood. Unfortunately, tonight’s events had been anything but playful, and there had been nothing mischievous about the seriousness with which Peter had urged Langdon to protect the sealed package in his daybag.

Langdon glanced forlornly at the plastic bag containing Peter’s gold ring. “Director,” he asked, “would you mind if I held on to this?”

She looked over. “Why?”

“It’s very valuable to Peter, and I’d like to return it to him tonight.”

She looked skeptical. “Let’s hope you get that chance.”

“Thanks.” Langdon pocketed the ring.

“Another question,” Sato said as they hastened deeper into the labyrinth. “My staff said that while cross-checking the concepts of the ‘thirty-third degree’ and ‘portal’ with Masonry, they turned up literally hundreds of references to a ‘pyramid’?”

“That’s not surprising, either,” Langdon said. “The pyramid builders of Egypt are the forerunners of the modern stonemasons, and the pyramid, along with Egyptian themes, is very common in Masonic symbolism.”

“Symbolizing what?”

“The pyramid essentially represents enlightenment. It’s an architectural symbol emblematic of ancient man’s ability to break free from his earthly plane and ascend upward toward heaven, toward the golden sun, and ultimately, toward the supreme source of illumination.”

She waited a moment. “Nothing else?”

Nothing else?! Langdon had just described one of history’s most elegant symbols. The structure through which man elevated himself into the realm of the gods.

“According to my staff,” she said, “it sounds like there is a much more relevant connection tonight. They tell me there exists a popular legend about a specific pyramid here in Washington—a pyramid that relates specifically to the Masons and the Ancient Mysteries?”

Langdon now realized what she was referring to, and he tried to dispel the notion before they wasted any more time. “I am familiar with the legend, Director, but it’s pure fantasy. The Masonic Pyramid is one of D.C.’s most enduring myths, probably stemming from the pyramid on the Great Seal of the United States.”

“Why didn’t you mention it earlier?”

Langdon shrugged. “Because it has no basis in fact. Like I said, it’s a myth. One of many associated with the Masons.”

“And yet this particular myth relates directly to the Ancient Mysteries?”

“Sure, as do plenty of others. The Ancient Mysteries are the foundation for countless legends that have survived in history—stories about powerful wisdom protected by secret guardians like the Templars, the Rosicrucians, the Illuminati, the Alumbrados—the list goes on and on. They are all based on the Ancient Mysteries . . . and the Masonic Pyramid is just one example.”

“I see,” Sato said. “And what does this legend actually say?”

Langdon considered it for a few steps and then replied, “Well, I’m no specialist in conspiracy theory, but I am educated in mythology, and most accounts go something like this: The Ancient Mysteries—the lost wisdom of the ages—have long been considered mankind’s most sacred treasure, and like all great treasures, they have been carefully protected. The enlightened sages who understood the true power of this wisdom learned to fear its awesome potential. They knew that if this secret knowledge were to fall into uninitiated hands, the results could be devastating; as we said earlier, powerful tools can be used either for good or for evil. So, in order to protect the Ancient Mysteries, and mankind in the process, the early practitioners formed secret fraternities. Inside these brotherhoods, they shared their wisdom only with the properly initiated, passing the wisdom from sage to sage. Many believe we can look back and see the historical remnants of those who mastered the Mysteries . . . in the stories of sorcerers, magicians, and healers.”

“And the Masonic Pyramid?” Sato asked. “How does that fit in?”

“Well,” Langdon said, striding faster now to keep pace, “this is where history and myth begin to merge. According to some accounts, by the sixteenth century in Europe, almost all of these secret fraternities had become extinct, most of them exterminated by a growing tide of religious persecution. The Freemasons, it is said, became the last surviving custodians of the Ancient Mysteries. Understandably, they feared that if their own brotherhood one day died off like its predecessors, the Ancient Mysteries would be lost for all time.”

“And the pyramid?” Sato again pressed.

Langdon was getting to it. “The legend of the Masonic Pyramid is quite simple. It states that the Masons, in order to fulfill their responsibility of protecting this great wisdom for future generations, decided to hide it in a great fortress.” Langdon tried to gather his recollections of the story. “Again, I stress this is all myth, but allegedly, the Masons transported their secret wisdom from the Old World to the New World—here, to America—a land they hoped would remain free from religious tyranny. And here they built an impenetrable fortress—a hidden pyramid—designed to protect the Ancient Mysteries until the time that all of mankind was ready to handle the awesome power that this wisdom could communicate. According to the myth, the Masons crowned their great pyramid with a shining, solid-gold capstone as symbol of the precious treasure within—the ancient wisdom capable of empowering mankind to his full human potential. Apotheosis.”

“Quite a story,” Sato said.

“Yes. The Masons fall victim to all kinds of crazy legends.”

“Obviously you don’t believe such a pyramid exists.”

“Of course not,” Langdon replied. “There’s no evidence whatsoever to suggest that our Masonic forefathers built any kind of pyramid in America, much less in D.C. It’s pretty difficult to hide a pyramid, especially one large enough to hold all the lost wisdom of the ages.”

The legend, as Langdon recalled, never explained exactly what was supposed to be inside the Masonic Pyramid—whether it was ancient texts, occult writings, scientific revelations, or something far more mysterious—but the legend did say that the precious information inside was ingeniously encoded . . . and understandable only to the most enlightened souls.

“Anyway,” Langdon said, “this story falls into a category we symbologists call an ‘archetypal hybrid’—a blend of other classic legends, borrowing so many elements from popular mythology that it could only be a fictional construct . . . not historical fact.”

When Langdon taught his students about archetypal hybrids, he used the example of fairy tales, which were recounted across generations and exaggerated over time, borrowing so heavily from one another that they evolved into homogenized morality tales with the same iconic elements—virginal damsels, handsome princes, impenetrable fortresses, and powerful wizards. By way of fairy tales, this primeval battle of “good vs. evil” is ingrained into us as children through our stories: Merlin vs. Morgan le Fay, Saint George vs. the Dragon, David vs. Goliath, Snow White vs. the Witch, and even Luke Skywalker battling Darth Vader.

Sato scratched her head as they turned a corner and followed Anderson down a short flight of stairs. “Tell me this. If I’m not mistaken, pyramids were once considered mystical portals through which the deceased pharaohs could ascend to the gods, were they not?”

“True.”

Sato stopped short and caught Langdon’s arm, glaring up at him with an expression somewhere between surprise and disbelief. “You’re saying Peter Solomon’s captor told you to find a hidden portal, and it didn’t occur to you that he was talking about the Masonic Pyramid from this legend?”

“By any name, the Masonic Pyramid is a fairy tale. It’s purely fantasy.”

Sato stepped closer to him now, and Langdon could smell her cigarette breath. “I understand your position on that, Professor, but for the sake of my investigation, the parallel is hard to ignore. A portal leading to secret knowledge? To my ear, this sounds a lot like what Peter Solomon’s captor claims you, alone, can unlock.”

“Well, I can hardly believe—”

“What you believe is not the point. No matter what you believe, you must concede that this man might himself believe that the Masonic Pyramid is real.”

“The man’s a lunatic! He may well believe that SBB Thirteen is the entrance to a giant underground pyramid that contains all the lost wisdom of the ancients!”

Sato stood perfectly still, her eyes seething. “The crisis I am facing tonight is not a fairy tale, Professor. It is quite real, I assure you.”

A cold silence hung between them.

“Ma’am?” Anderson finally said, gesturing to another secure door ten feet away. “We’re almost there, if you’d like to continue.” Sato finally broke eye contact with Langdon, motioning for Anderson to move on. They followed the security chief through the secure doorway, which deposited them in a narrow passage. Langdon looked left and then right.

You’ve got to be kidding.

He was standing in the longest hallway he had ever seen.