atherine Solomon’s heart felt light as she hurried up the hill toward the base of the Washington Monument. She had endured great shock and tragedy tonight, and yet her thoughts were refocused now, if only temporarily, on the wonderful news Peter had shared with her earlier . . . news she had just confirmed with her very own eyes.

My research is safe. All of it.

Her lab’s holographic data drives had been destroyed tonight, but earlier, at the House of the Temple, Peter had informed her that he had been secretly keeping backups of all her Noetic research in the SMSC executive offices. You know I’m utterly fascinated with your work, he had explained, and I wanted to follow your progress without disturbing you.

“Katherine?” a deep voice called out.

She looked up.

A lone figure stood in silhouette at the base of the illuminated monument.

“Robert!” She hurried over and hugged him.

“I heard the good news,” Langdon whispered. “You must be relieved.”

Her voice cracked with emotion. “Incredibly.” The research Peter had saved was a scientific tour de force—a massive collection of experiments that proved human thought was a real and measurable force in the world. Katherine’s experiments demonstrated the effect of human thought on everything from ice crystals to random-event generators to the movement of subatomic particles. The results were conclusive and irrefutable, with the potential to transform skeptics into believers and affect global consciousness on a massive scale. “Everything is going to change, Robert. Everything.”

“Peter certainly thinks so.”

Katherine glanced around for her brother.

“Hospital,” Langdon said. “I insisted he go as a favor to me.”

Katherine exhaled, relieved. “Thank you.”

“He told me to wait for you here.”

Katherine nodded, her gaze climbing the glowing white obelisk. “He said he was bringing you here. Something about ‘Laus Deo’? He didn’t elaborate.”

Langdon gave a tired chuckle. “I’m not sure I entirely understand it myself.” He glanced up at the top of the monument. “Your brother said quite a few things tonight that I couldn’t get my mind around.”

“Let me guess,” Katherine said. “Ancient Mysteries, science, and the Holy Scriptures?”

“Bingo.”

“Welcome to my world.” She winked. “Peter initiated me into this long ago. It fueled a lot of my research.”

“Intuitively, some of what he said made sense.” Langdon shook his head. “But intellectually . . .”

Katherine smiled and put her arm around him. “You know, Robert, I may be able to help you with that.”

Deep inside the Capitol Building, Architect Warren Bellamy was walking down a deserted hallway.

Only one thing left to do tonight, he thought.

When he arrived at his office, he retrieved a very old key from his desk drawer. The key was black iron, long and slender, with faded markings. He slid it into his pocket and then prepared himself to welcome his guests.

Robert Langdon and Katherine Solomon were on their way to the Capitol. At Peter’s request, Bellamy was to provide them with a very rare opportunity—the chance to lay eyes upon this building’s most magnificent secret . . . something that could be revealed only by the Architect.