obert Langdon stood mesmerized at the glass portal, absorbing the power of the landscape below him. Having ascended unknowingly hundreds of feet into the air, he was now admiring one of the most spectacular vistas he had ever seen.

The shining dome of the U.S. Capitol rose like a mountain at the east end of the National Mall. On either side of the building, two parallel lines of light stretched toward him . . . the illuminated facades of the Smithsonian museums . . . beacons of art, history, science, culture.

Langdon now realized to his astonishment that much of what Peter had declared to be true . . . was in fact true. There is indeed a winding staircase . . . descending hundreds of feet beneath a massive stone. The huge capstone of this obelisk sat directly over his head, and Langdon now recalled a forgotten bit of trivia that seemed to have eerie relevance: the capstone of the Washington Monument weighed precisely thirty-three hundred pounds.

Again, the number 33.

More startling, however, was the knowledge that this capstone’s ultimate peak, the zenith of this obelisk, was crowned by a tiny, polished tip of aluminum—a metal as precious as gold in its day. The shining apex of the Washington Monument was only about a foot tall, the same size as the Masonic Pyramid. Incredibly, this small metal pyramid bore a famous engraving—Laus Deo— and Langdon suddenly understood. This is the true message of the base of the stone pyramid.

The seven symbols are a transliteration!

“Laus Deo,” Langdon whispered. The well-known Latin phrase—meaning “praise God”—was inscribed on the tip of the Washington Monument in script letters only one inch tall. On full display . . . and yet invisible to all.

“Praise God,” Peter said behind him, flipping on the soft lighting in the chamber. “The Masonic Pyramid’s final code.”

Langdon turned. His friend was grinning broadly, and Langdon recalled that Peter had actually spoken the words “praise God” earlier inside the Masonic library. And I still missed it.

Langdon felt a chill to realize how apt it was that the legendary Masonic Pyramid had guided him here . . . to America’s great obelisk—the symbol of ancient mystical wisdom—rising toward the heavens at the heart of a nation.

In a state of wonder, Langdon began moving counterclockwise around the perimeter of the tiny square room, arriving now at another viewing window.

Through this northward-facing window, Langdon gazed down at the familiar silhouette of the White House directly in front of him. He raised his eyes to the horizon, where the straight line of Sixteenth Street ran due north toward the House of the Temple.

I am due south of Heredom.

He continued around the perimeter to the next window. Looking west, Langdon’s eyes traced the long rectangle of the reflecting pool to the Lincoln Memorial, its classical Greek architecture inspired by the Parthenon in Athens, Temple to Athena—goddess of heroic undertakings.

Annuit coeptis, Langdon thought. God favors our undertaking.

Continuing to the final window, Langdon gazed southward across the dark waters of the Tidal Basin, where the Jefferson Memorial shone brightly in the night. The gently sloping cupola, Langdon knew, was modeled after the Pantheon, the original home to the great Roman gods of mythology.

Having looked in all four directions, Langdon now thought about the aerial photos he had seen of the National Mall—her four arms outstretched from the Washington Monument toward the cardinal points of the compass. I am standing at the crossroads of America.

Langdon continued back around to where Peter was standing. His mentor was beaming. “Well, Robert, this is it. The Lost Word. This is where it’s buried. The Masonic Pyramid led us here.”

Langdon did a double take. He had all but forgotten about the Lost Word.

“Robert, I know of nobody more trustworthy than you. And after a night like tonight, I believe you deserve to know what this is all about. As promised in legend, the Lost Word is indeed buried at the bottom of a winding staircase.” He motioned to the mouth of the monument’s long stairwell.

Langdon had finally started to get his feet back under him, but now he was puzzled.

Peter quickly reached into his pocket and pulled out a small object. “Do you remember this?”

Langdon took the cube-shaped box that Peter had entrusted to him long ago. “Yes . . . but I’m afraid I didn’t do a very good job of protecting it.”

Solomon chuckled. “Perhaps the time had come for it to see the light of day.”

Langdon eyed the stone cube, wondering why Peter had just handed it to him.

“What does this look like to you?” Peter asked.

Langdon eyed the 1514 and recalled his first impression when Katherine had unwrapped the package. “A cornerstone.”

“Exactly,” Peter replied. “Now, there are a few things you might not know about cornerstones. First, the concept of laying a cornerstone comes from the Old Testament.”

Langdon nodded. “The Book of Psalms.”

“Correct. And a true cornerstone is always buried beneath the ground—symbolizing the building’s initial step upward out of the earth toward the heavenly light.”

Langdon glanced out at the Capitol, recalling that its cornerstone was buried so deep in the foundation that, to this day, excavations had been unable to find it.

“And finally,” Solomon said, “like the stone box in your hand, many cornerstones are little vaults . . . and have hollow cavities so that they can hold buried treasures . . . talismans, if you will—symbols of hope for the future of the building about to be erected.”

Langdon was well aware of this tradition, too. Even today, Masons laid cornerstones in which they sealed meaningful objects—time capsules, photos, proclamations, even the ashes of important people.

“My purpose in telling you this,” Solomon said, glancing over at the stairwell, “should be clear.”

“You think the Lost Word is buried in the cornerstone of the Washington Monument?”

“I don’t think, Robert. I know. The Lost Word was buried in the cornerstone of this monument on July 4, 1848, in a full Masonic ritual.”

Langdon stared at him. “Our Masonic forefathers buried a word?!”

Peter nodded. “They did indeed. They understood the true power of what they were burying.”

All night, Langdon had been trying to wrap his mind around sprawling, ethereal concepts . . . the Ancient Mysteries, the Lost Word, the Secrets of the Ages. He wanted something solid, and despite Peter’s claims that the key to it all was buried in a cornerstone 555 feet beneath him, Langdon was having a hard time accepting it. People study the mysteries for entire lifetimes and are still unable to access the power allegedly hidden there. Langdon flashed on Dürer’s Melencolia I—the image of the dejected Adept, surrounded by the tools of his failed efforts to unveil the mystical secrets of alchemy. If the secrets can actually be unlocked, they will not be found in one place!

Any answer, Langdon had always believed, was spread across the world in thousands of volumes . . . encoded into writings of Pythagoras, Hermes, Heraclitus, Paracelsus, and hundreds of others. The answer was found in dusty, forgotten tomes on alchemy, mysticism, magic, and philosophy. The answer was hidden in the ancient library of Alexandria, the clay tablets of Sumer, and the hieroglyphs of Egypt.

“Peter, I’m sorry,” Langdon said quietly, shaking his head. “To understand the Ancient Mysteries is a lifelong process. I can’t imagine how the key could possibly rest within a single word.”

Peter placed a hand on Langdon’s shoulder. “Robert, the Lost Word is not a ‘word.’” He gave a sage smile. “We only call it the ‘Word’ because that’s what the ancients called it . . . in the beginning.”