Ambra looked hopeful. “Edmond said his favorite line of poetry was a prophecy that he hoped would come true.”

“Well,” Langdon said, “a future without religion is certainly something Edmond wanted. How many letters in that line?”

Ambra began counting but shook her head. “Over fifty.”

She returned to skimming the poem, pausing a moment later. “How about this one? ‘The Expanding eyes of Man behold the depths of wondrous worlds.’ ”

“Possible,” Langdon said, pondering its meaning. Human intellect will continue to grow and evolve over time, enabling us to see more deeply into the truth.

“Too many letters again,” Ambra said. “I’ll keep going.”

As she continued down the page, Langdon began pacing pensively behind her. The lines she’d already read echoed in his mind and conjured a distant memory of his reading Blake in a Princeton “Brit lit” class.

Images began forming, as sometimes happened with Langdon’s eidetic memory. These images conjured new images, in endless succession. Suddenly, standing in the crypt, Langdon flashed on his professor, who, upon the class’s completion of The Four Zoas, stood before them and asked the age-old questions: Which would you choose? A world without religion? Or a world without science? Then the professor had added: Clearly, William Blake had a preference, and nowhere is his hope for the future better summarized than in the final line of this epic poem.

Langdon drew a startled breath and spun toward Ambra, who was still poring over Blake’s text.

“Ambra—skip down to the end of the poem!” he said, now recalling the poem’s final line.

Ambra looked to the end of the poem. After focusing a moment, she turned back to him with an expression of wide-eyed disbelief.

Langdon joined her at the book, peering down at the text. Now that he knew the line, he was able to make out the faint handwritten letters:

The dark religions are departed & sweet science reigns.

“‘The dark religions are departed,’” Ambra read aloud. “‘And sweet science reigns.’”

The line was not only a prophecy that Edmond would endorse, it was essentially a synopsis of his presentation earlier tonight.

Religions will fade … and science will rule.

Ambra began carefully counting the letters in the line, but Langdon knew it was unnecessary. This is it. No doubt. His mind had already turned to accessing Winston and launching Edmond’s presentation. Langdon’s plan for how to make that happen was something he would need to explain to Ambra in private.

He turned to Father Beña, who was just returning. “Father?” he asked. “We’re almost done here. Would you mind going upstairs and telling the Guardia agents to summon the helicopter? We’ll need to leave at once.”

“Of course,” Beña said, and headed up the stairs. “I hope you found what you came for. I’ll see you upstairs in a moment.”

As the priest disappeared up the stairs, Ambra turned away from the book with a look of sudden alarm.

“Robert,” she said. “This line is too short. I counted it twice. It’s only forty-six letters. We need forty-seven.”

“What?” Langdon walked over to her, squinting at the text and carefully counting each handwritten letter. “The dark religions are departed & sweet science reigns.” Sure enough, he arrived at forty-six. Baffled, he studied the line again. “Edmond definitely said forty-seven, not forty-six?”

“Absolutely.”

Langdon reread the line. But this must be it, he thought. What am I missing?

Carefully, he scanned every letter in the final line of Blake’s poem. He was almost to the end when he saw it.

… & sweet science reigns.

“The ampersand,” Langdon blurted. “The symbol Blake used instead of writing out the word ‘and.’”

Ambra eyed him strangely and then shook her head. “Robert, if we substitute the word ‘and’ … then the line has forty-eight letters. Too many.”

Not true. Langdon smiled. It’s a code within a code.

Langdon marveled at Edmond’s cunning little twist. The paranoid genius had used a simple typographic trick to ensure that even if someone discovered which line of poetry was his favorite, they would still not be able to type it correctly.

The ampersand code, Langdon thought. Edmond remembered it.

The origin of the ampersand was always one of the first things Langdon taught his symbology classes. The symbol “&” was a logogram—literally a picture representing a word. While many people assumed the symbol derived from the English word “and,” it actually derived from the Latin word et. The ampersand’s unusual design “&” was a typographical fusion of the letters E and T—the ligature still visible today in computer fonts like Trebuchet, whose ampersand “&” clearly echoed its Latin origin.

Langdon would never forget that the week after he had taught Edmond’s class about the ampersand, the young genius had shown up wearing a T-shirt printed with the message—Ampersand phone home!—a playful allusion to the Spielberg movie about an extraterrestrial named “ET” who was trying to find his way home.

Now, standing over Blake’s poem, Langdon was able to picture Edmond’s forty-seven-letter password perfectly in his mind.

thedarkreligionsaredepartedetsweetsciencereigns

Quintessential Edmond, Langdon thought, quickly sharing with Ambra the clever trick Edmond had used to add a level of security to his password.