It was there that I began to lose consciousness.

Several massive pillars constituted an entrance that rose almost to the water's surface. I swam between them and into an aquatic ecosystem unlike any I had ever seen.

Despite its depths, the reef was filled with life more commonly seen nearer the surface. The pillars were coated with algae. A network of fish and other shallow-water sea creatures wove around them. I watched a school of fish and came slowly to the realization that the organisms within the Smoky Reef lacked natural competition. They benefited from an increase in physical space, fewer predators, and more abundant food. They bore a biological advantage.

But why are they here at all?

I could feel why. The area was unnaturally warm. The deeper within its depths I swam, the more its heat enveloped me, like the warmth of a coral reef. But instead of the sun above, the Smoky Reef's heat source was constant volcanic activity from below.

I swam deeper.

The giant pillars and the life forms housed within them indeed shared a smoky appearance. I allowed my eyes to trace the grayish lines of sulfur deposits streaking the surfaces of the pillars, and I was able to detect the active fumaroles that bubbled gently around them. I collected several more samples.

My work completed to my satisfaction, I turned to return to the boat. It was then that I first noticed how lightheaded I had become.

I stopped swimming for a moment and looked around in an effort to regain my bearings. I realized I had no idea where the boat was. I began swimming aimlessly, but my limbs felt heavy. I was suddenly so, so tired. I just wanted to sleep. More than anything. I needed to sleep.

I changed directions, and suddenly there before me was Alyssa. In slow motion, she grabbed my arm and looked into my face. Behind her scuba mask, her green eyes flashed. She disappeared behind me, and then a thin arm slithered around my waist from the direction she had gone.

No longer caring, I allowed myself to drift into unconsciousness.

I still have three years of graduate school left, and the bullet comes crashing through the living room window.

And then Christopher, my baby, my five-year-old little boy, is bleeding to death in my arms.

I awoke lying on my side, vomiting. My joints were burning. Each involuntary heave of my stomach sent another jolt of fire through them.

"Welcome back, signora," a man said. His accent was Italian. An Italian accent sounded familiar, but I could not remember where I had recently heard one.

The waves of convulsions in my stomach finally subsided, and I rolled over onto my back. Slowly, a vertical staff wound with symmetrical snakes came into focus. The man's uniform bore a caduceus, the eternal symbol of medicine, and behind the man was a dilapidated ambulance.

The medic looked up from examining me, his gaze directed over my head, and said something in Italian. An angry female voice answered. From the depths of a cave, I remembered that voice. It was Alyssa Iacovani's. I turned my head and looked toward her.

Alyssa's eyes fell upon me as a large rubber bowl descended over my nose and mouth. "It's one hundred percent oxygen," she said. "You lost consciousness, and I had to rush you to the surface. Now you have the bends and will need decompression. I'm sorry, Katrina."

I nodded.

Slowly, carefully, I sat up. The pain in my joints was almost unbearable.

"Be careful," Alyssa said.

I reached up and pulled the oxygen mask away from my mouth so that I could speak. "The tank..." I said weakly, and I forced myself to turn and scan the area for my scuba apparatus.

"I'm sorry, ma'am," another voice said, this one in perfect English. "You can rest assured we will conduct a thorough investigation into what might have caused your gear to malfunction. This is the first incident of this kind that our diving company has ever experienced. The safety of our customers is paramount."

I realized then that there was another man standing over me in addition to the medic. The second man's smile was unnaturally wide, and he was sweating profusely. His eyes reminded me of the eyes of a reptile.

"No!" Alyssa said sharply. "You will listen to me! This is a prominent American doctor with connections to Homeland Security. She almost died in your company's care. You will give me the fucking tank. Right now."

I was rolled onto a stretcher, lifted into the ambulance, and then carried into a hospital and placed in a pressure chamber. There I remained for almost five hours as the nitrogen content in my bloodstream slowly normalized. When I emerged, I felt almost normal.

"We need to keep you overnight for observation, signora," a man said as I began gathering my belongings.

"You almost have," Alyssa said. "Step aside."

He stepped toward her as if to prevent us from leaving, but the blaze in her green eyes made him stop. He stepped backward.

Alyssa led me to her car. Once we were alone inside it, I finally asked the question that had been running through my mind. "What are the odds that this was an accident?"

"Under normal circumstances," Alyssa said, "I would say huge. Safety regulations aren't the same in Italy as they are in the United States. These things happen. Tour buses fall off cliffs all the time. Trains derail. But lately, I don't assume anything is an accident."

"My thoughts exactly," I said. "Thank you for saving me. And for making sure we got the tank. It will only take a few minutes in a laboratory for me to understand what I was actually breathing down there."

But first, I needed the laboratory.

I turned to survey the back seat of the car. It was all but overflowing with biological samples, and the trunk was full as well. Each of the unique chemical environments that I had sampled in just one afternoon would exponentially expand my work load.

"Alyssa, I can begin the analysis of these samples immediately if I can have access to a lab, but I need at least a skeleton staff to operate it. I need a basic molecular biology facility and a basic organic chemistry facility. And I need help, especially on the chemistry side, from people who know what they are doing and won't ask too many questions. Can you get me these things?"

"You already have them," she said.

For the poor people from the streets near the di Sangro Chapel, the Neapolitan incarnation of Dr. Faustus made a pact with the devil, and almost became a devil himself, to master the most secret mysteries of nature.

-Storie e Leggende Napoletane Benedetto Croce (18661952)

Chapter Fourteen.

It was nearly two in the morning when we finally returned to Naples. The trunk of Alyssa's car was loaded with plastic bags and containers holding more than one hundred biological samples, their labels providing an itinerary of every location we had visited. I had gathered dry dirt, boiling mud, steam that had now condensed into liquid, seawater, and sulfuric deposits from cave walls. I had even collected air, in the form of millions of tiny gaseous bubbles emerging from the sea floor.

Spiraling around me now were the millions of tasks ahead of me. Each sample mandated a new data set, each data set a new analysis. And now I had reason to analyze the contents of a scuba tank as well.

Still, I was eager to begin the analyses of the samples and also curious about the labs themselves. "Where did these labs come from?" I asked.

"The labs are mine, sort of," Alyssa said. "I began setting them up when I first found the nardo document. With all the strange things that kept happening to me, I wanted to keep the document away from the rest of the Piso Project team at the archeological museum. So I pulled some strings and secured a separate location for a research facility. It's in the basement beneath another museum, the Cappella Sansevero. I have known the curator there for years; he is a good friend.

"I have been very interested in the Sansevero since I began working on the Piso Project. I'm even more interested in it now that I've found the nardo document."

"Why?" I asked.

"Because the chapel is a shrine to our isotope."

We pulled into a narrow, crooked alleyway in the heart of Naples, and Alyssa parked the car. "Just leave the samples here for now," she said. "We can grab some big trash bags from inside to carry them in."

We exited the car and began walking through the alley.

"The Villa dei Papiri was first rediscovered in the 1700s, after nearly two thousand years beneath the ash," Alyssa said. "The king of Naples at that time was Charles of Bourbon. Raimondo di Sangro, the Prince of Sansevero and patron of this chapel, was a good friend of his. Charles enlisted di Sangro to attempt the unrolling and deciphering of the papyrus scrolls."

"And?"

"Di Sangro tried using mercury to soften the charred papyrus."

"What was the result?" I asked.

"The scrolls dissolved."

"Damn."

"I'll say."

We approached a nondescript brown building. A molded archway surrounded a heavy wooden door. Alyssa produced a key, and we entered the building. Inside was an information and ticketing desk for the museum, but at that late hour it was vacant. A tall A-frame sign announced the entrance to the Sansevero chapel.

"Raimondo di Sangro was one of the first people to become truly obsessed with the documents buried within the Villa dei Papiri. And I believe he was searching for the same thing we are searching for. He was clearly onto something resembling our isotope. But I'm not sure if he found it."

"How close did he come?"

"Much closer than we are."

Alyssa pushed open a second heavy wooden door, and we entered di Sangro's chapel.

The moment I saw what was inside, I sucked in my breath and stopped short. I could make no sound. I could only stare. I have no idea how long I stood there.

My mind was not my own as I stepped forward.

Beneath the altar was a single prominent display-whispering, seducing, drawing me toward it. I approached it with no free will to do otherwise.

A display case of clear glass enclosed a body. Inside the glass was Jesus Christ.

He was lying on his back, his face tilted to one side, his eyes closed. Beneath him was a thick, fluffy, padded bed, and his upper body was propped upon two soft pillows. His entire body, from head to toe, was covered with a thin, transparent veil. Its gentle folds were spun from a silken cloth so delicate that Christ's every feature, every muscle, every detail of face and body could be clearly discerned beneath it.

But it was not cloth. It was marble. The soft shroud, the warm and comforting bed, the perfect body, and the peaceful face-the entire masterpiece had been freed from within a single slab of marble.

The expression on Christ's face was one of serenity. He appeared to be sleeping rather than dead, and the sense of peace he projected contrasted sharply with the broken shackles and crown of thorns lying near his feet. These objects of torture from his mortal life lay next to the body but outside of the veil, as if rejected from the warm cocoon protecting the Savior.

Christ's body was thin but not emaciated as I had seen in so many depictions of this moment. His shoulders and biceps were muscular, the forearms and hands extending from them long and lean. His right arm lay gently alongside his body; the left was resting casually and comfortably upon his hip. The details of each finger could be observed from beneath the soft folds of the marble veil, and they spoke not of the pain of the cross but of the many miracles born from them. The rising arch of his chest sloped down into a flat abdomen, and I was almost certain that I could see him breathing beneath the veil.

"You share your husband's curiosity," Alyssa said softly from beside me. "Jeff had the same reaction."

"I have never seen anything so amazing," I whispered.

"It's entitled The Veiled Christ. It was created by Giuseppe Sanmartino at the behest of Raimondo di Sangro. It is sometimes also referred to as The Dead Christ."

"This Christ is not dead," I said. "He is the personification of vitality."

"You're absolutely right. He is awaiting the moment of resurrection."

I cast my eyes again upon the liquid veil and the perfect body beneath it. "How did Sanmartino do it?" I asked. "This could not possibly have been sculpted with a chisel."

"For over two hundred fifty years, the veil was believed to have been created by Raimondo di Sangro himself using some secret alchemy. But modern analyses have confirmed that it was in fact done with a chisel. Legend also held that di Sangro gouged out the eyes of Giuseppe Sanmartino, after Sanmartino completed this work, so that he would never again be able to create something so beautiful. Of course, the fact that Sanmartino sculpted many other pieces later in life disproves this myth pretty definitively. None of his subsequent works compare to this one, but certainly they were not carved by a blind man."

I laughed softly. "Then why would people have thought that of di Sangro?" I asked.

"Such was the reputation of the Prince of Sansevero."

Alyssa began walking as she continued. "Raimondo di Sangro was the Grand Master of the Neapolitan Freemasons. He did not build this chapel, but in the last years of his life he completely remodeled it into a tribute to his beliefs.

"Unlike many of his contemporaries and other art patrons through the ages, di Sangro maintained full control over the artwork in this chapel. Rather than giving a rough idea of what he was looking for and then leaving it to the artist's imagination, he gave very specific instructions as to how he wanted his own thoughts expressed in each piece. Many of the things in this room were literally done by di Sangro's own hand. The rest of the pieces are his visions.

"This whole section is filled with statues of the virtues. Among them are Modesty, Divine Love, Self-control, Liberality, Religious Zeal, and Education. When we have more time, I can explain all of them to you if you like. But this one is important."

She directed my attention to a statue almost as impressive as The Veiled Christ. But rather than a thin, transparent veil, the central figure in this one was enveloped within a binding net. And unlike the Christ, at peace beneath his veil, this figure was struggling to escape. He was assisted by a small spirit bearing a flame on his forehead. At the feet of the two figures were a globe and an open Bible. I marveled at the intricacy of the netting that ensnared the man, and I was stunned-once again-that such a feat could be attained in marble with a chisel.

"There was a triad including this piece and The Veiled Christ," Alyssa continued. "They were the masterpieces, devoted to artistic excellence."

She pointed to the bas relief on the pedestal. "The Bible is open to the story of Jesus restoring sight to the blind. But this piece is entitled Disillusion. It refers to the very Masonic idea of light from the darkness, an obvious metaphor for knowledge.

"Di Sangro was a follower of Enlightenment principles, but like so many of his era he was stifled by the Church over the course of his lifetime. One of the more well-studied essays he wrote, his Lettera Apologetica, communicated some of the more radical Enlightenment notions, including free thought and hostility toward Church interference. Of course, the Church was mortified. They banned it."

"But wouldn't di Sangro have actually been a member of the Church?" I asked.

"Publicly, yes, of course. But he was also believed to be a Rosicrucian."

I squinted. "Which means what, exactly?"

"Rosicrucianism is a... I hate to even use the word religion... it's a philosophy. The order was founded by a circle of doctors. Like the Freemasons and so many other secret societies of the time, their purpose was, to put it in far overly simplistic terms, to learn-without the interference of the Church.

"There is a Rosicrucian maxim: to know, to will, to dare, and to keep silent. Di Sangro seems to have lived by it. He studied the arts, philosophy, military tactics, printing presses, pyrotechnics, physics, pharmaceuticals, mechanics, you name it. His scientific work was at the cutting edge of several fields, including the budding transition from alchemy to modern chemistry. Indeed, he was one of the preeminent scientists to make that transition.

"Di Sangro created this chapel to showcase his accomplishments. But his work was secret, and his laboratories were secret. And just before he died, he burned all of his research. So there are many things to this day that we know he did, but nobody has any idea how he did them."

"Sounds like Cleopatra burning her own library down after hiding her most critical documents in other locations," I observed.

"He was like Cleopatra in almost every way," Alyssa agreed. "He had an appetite for the sciences and spoke and wrote fluently in multiple languages. He was completely secretive about his work, and very deliberate in choosing which messages to share publicly. But he left tributes in plain sight so the very enlightened could see them. And that is why I think we can find the isotope through him."

I stepped away from Disillusioned and began surveying more of the chapel. In my compulsion to reach the sculpture of Christ, I had scarcely noticed the chapel's details upon first entering. Now, they were critical.

"What parts of this chapel are works of di Sangro's own hand?" I asked.

Alyssa took my arm and led me back toward the entrance before pointing to the amazing frescoed ceiling.

"Look at the colors," she said. "Di Sangro didn't paint the ceiling, but he invented the paints. Nobody understands how they have remained so well preserved for so long. Baroque period frescoes never look this good unless they have been actively restored. Except for this one. It's timeless."

We then stepped into a small alcove along the side of the chapel, and I realized I was looking at di Sangro's tomb.