“Non ce l’ho,” he managed. I don’t have the key.

The tall man advanced past them to the grating and examined the mechanism. “It’s a combination lock,” he called back to the woman, his accent American.

The woman knelt down next to Ernesto, her brown eyes like ice. “Qual è la combinazione?” she demanded.

“Non posso!” he replied. “I’m not permitted—”

Something happened at the top of his spine, and Ernesto felt his entire body go limp. An instant later, he blacked out.

When he came to, Ernesto sensed he had been drifting in and out of consciousness for several minutes. He recalled some discussion … more stabs of pain … being dragged, perhaps? It was all a blur.

As the cobwebs cleared, he saw a strange sight—his shoes lying on the floor nearby with their laces removed. It was then that he realized he could barely move. He was lying on his side with his hands and feet bound behind him, apparently with his shoelaces. He tried to yell, but no sound came. One of his own socks was stuffed in his mouth. The true moment of fear, however, came an instant later, when he looked up and saw his television set playing the football match. I’m in my office … INSIDE the grate?!

In the distance, Ernesto could hear the sound of running footsteps departing along the corridor … and then, slowly, they faded to silence. Non è possibile! Somehow, the blond woman had persuaded Ernesto to do the one thing he was hired never to do—reveal the combination for the lock on the entrance to the famed Vasari Corridor.

CHAPTER 31

Dr. Elizabeth Sinskey felt the waves of nausea and dizziness coming faster now. She was slumped in the backseat of the van parked in front of the Pitti Palace. The soldier seated beside her was watching her with growing concern.

Moments earlier, the soldier’s radio had blared—something about a costume gallery—awakening Elizabeth from the darkness of her mind, where she had been dreaming of the green-eyed monster.

She had been back in the darkened room at the Council on Foreign Relations in New York, listening to the maniacal ravings of the mysterious stranger who had summoned her there. The shadowy man paced at the front of the room—a lanky silhouette against the grisly projected image of the naked and dying throngs inspired by Dante’s Inferno.

“Someone needs to fight this war,” the figure concluded, “or this is our future. Mathematics guarantees it. Mankind is hovering now in a purgatory of procrastination and indecision and personal greed … but the rings of hell await, just beneath our feet, waiting to consume us all.”

Elizabeth was still reeling from the monstrous ideas this man had just laid out before her. She could stand it no longer and jumped to her feet. “What you’re suggesting is—”

“Our only remaining option,” the man interjected.

“Actually,” she replied, “I was going to say ‘criminal’!”

The man shrugged. “The path to paradise passes directly through hell. Dante taught us that.”

“You’re mad!”

“Mad?” the man repeated, sounding hurt. “Me? I think not. Madness is the WHO staring into the abyss and denying it is there. Madness is an ostrich who sticks her head in the sand while a pack of hyenas closes in around her.”

Before Elizabeth could defend her organization, the man had changed the image on the screen.

“And speaking of hyenas,” he said, pointing to the new image. “Here is the pack of hyenas currently circling humankind … and they are closing in fast.”

Elizabeth was surprised to see the familiar image before her. It was a graph published by the WHO the previous year delineating key environmental issues deemed by the WHO to have the greatest impact on global health.

The list included, among others:

Demand for clean water, global surface temperatures, ozone depletion, consumption of ocean resources, species extinction, CO2 concentration, deforestation, and global sea levels.

All of these negative indicators had been on the rise over the last century. Now, however, they were all accelerating at terrifying rates.

Elizabeth had the same reaction that she always had when she saw this graph—a sense of helplessness. She was a scientist and believed in the usefulness of statistics, and this graph painted a chilling picture not of the distant future … but of the very near future.

At many times in her life, Elizabeth Sinskey had been haunted by her inability to conceive a child. Yet, when she saw this graph, she almost felt relieved she had not brought a child into the world.

This is the future I would be giving my child?

“Over the last fifty years,” the tall man declared, “our sins against Mother Nature have grown exponentially.” He paused. “I fear for the soul of humankind. When the WHO published this graph, the world’s politicians, power brokers, and environmentalists held emergency summits, all trying to assess which of these problems were most severe and which we could actually hope to solve. The outcome? Privately, they put their heads in their hands and wept. Publicly, they assured us all that they were working on solutions but that these are complex issues.”

“These issues are complex!”

“Bullshit!” the man erupted. “You know damned well this graph depicts the simplest of relationships—a function based on a single variable! Every single line on this graph climbs in direct proportion to one value—the value that everyone is afraid to discuss. Global population!”

“Actually, I think it’s a bit more—”

“A bit more complicated? Actually, it’s not! There is nothing simpler. If you want more available clean water per capita, you need fewer people on earth. If you want to decrease vehicle emissions, you need fewer drivers. If you want the oceans to replenish their fish, you need fewer people eating fish!”

He glared down at her, his tone becoming even more forceful. “Open your eyes! We are on the brink of the end of humanity, and our world leaders are sitting in boardrooms commissioning studies on solar power, recycling, and hybrid automobiles? How is it that you—a highly educated woman of science—don’t see? Ozone depletion, lack of water, and pollution are not the disease—they are the symptoms. The disease is overpopulation. And unless we face world population head-on, we are doing nothing more than sticking a Band-Aid on a fast-growing cancerous tumor.”

“You perceive the human race as a cancer?” Elizabeth demanded.

“Cancer is nothing more than a healthy cell that starts replicating out of control. I realize you find my ideas distasteful, but I can assure you that you will find the alternative far less tasteful when it arrives. If we do not take bold action, then—”

“Bold?!” she sputtered. “Bold is not the word you’re looking for. Try insane!”

“Dr. Sinskey,” the man said, his voice now eerily calm. “I called you here specifically because I was hoping that you—a sage voice at the World Health Organization—might be willing to work with me and explore a possible solution.”

Elizabeth stared in disbelief. “You think the World Health Organization is going to partner with you … exploring an idea like this?”

“Actually, yes,” he said. “Your organization is made up of doctors, and when doctors have a patient with gangrene, they do not hesitate to cut off his leg to save his life. Sometimes the only course of action is the lesser of two evils.”

“This is quite different.”

“No. This is identical. The only difference is scale.”

Elizabeth had heard enough. She stood abruptly. “I have a plane to catch.”

The tall man took a threatening step in her direction, blocking her exit. “Fair warning. With or without your cooperation, I can very easily explore this idea on my own.”

“Fair warning,” she fired back. “I consider this a terrorist threat and will treat it as such.” She took out her phone.

The man laughed. “You’re going to report me for talking in hypotheticals? Unfortunately, you’ll have to wait to make your call. This room is electronically shielded. Your phone won’t have a signal.”

I don’t need a signal, you lunatic. Elizabeth raised her phone, and before the man realized what was happening, she clicked a snapshot of his face. The flash reflected in his green eyes, and for a moment she thought he looked familiar.

“Whoever you are,” she said, “you did the wrong thing by calling me here. By the time I reach the airport, I will know who you are, and you will be on the watch lists at the WHO, the CDC, and the ECDC as a potential bioterrorist. We will have people on you day and night. If you try to purchase materials, we will know about it. If you build a lab, we will know about it. There is nowhere you can hide.”

The man stood in tense silence for a long moment, as if he were going to lunge at her phone. Finally, he relaxed and stepped aside with an eerie grin. “Then it appears our dance has begun.”

CHAPTER 32

Il Corridoio Vasariano—the Vasari Corridor—was designed by Giorgio Vasari in 1564 under orders of the Medici ruler, Grand Duke Cosimo I, to provide safe passage from his residence at the Pitti Palace to his administrative offices, across the Arno River in the Palazzo Vecchio.

Similar to Vatican City’s famed Passetto, the Vasari Corridor was the quintessential secret passageway. It stretched nearly a full kilometer from the eastern corner of the Boboli Gardens to the heart of the old palace itself, crossing the Ponte Vecchio and snaking through the Uffizi Gallery in between.

Nowadays, the Vasari Corridor still served as a safe haven, although not for Medici aristocrats but for artwork; with its seemingly endless expanse of secure wall space, the corridor was home to countless rare paintings—overflow from the world-famous Uffizi Gallery, through which the corridor passed.

Langdon had traveled the passageway a few years before as part of a leisurely private tour. On that afternoon, he had paused to admire the corridor’s mind-boggling array of paintings—including the most extensive collection of self-portraits in the world. He had also stopped several times to peer out of the corridor’s occasional viewing portals, which permitted travelers to gauge their progress along the elevated walkway.

This morning, however, Langdon and Sienna were moving through the corridor at a run, eager to put as much distance as possible between themselves and their pursuers at the other end. Langdon wondered how long it would take for the bound guard to be discovered. As the tunnel stretched out before them, Langdon sensed it leading them closer with every step to what they were searching for.

Cerca trova … the eyes of death … and an answer as to who is chasing me.

The distant whine of the surveillance drone was far behind them now. The farther they progressed into the tunnel, the more Langdon was reminded of just how ambitious an architectural feat this passageway had been. Elevated above the city for nearly its entire length, the Vasari Corridor was like a broad serpent, snaking through the buildings, all the way from the Pitti Palace, across the Arno, into the heart of old Florence. The narrow, whitewashed passageway seemed to stretch for eternity, occasionally turning briefly left or right to avoid an obstacle, but always moving east … across the Arno.

The sudden sound of voices echoed ahead of them in the corridor, and Sienna skidded to a stop. Langdon halted, too, and immediately placed a calm hand on her shoulder, motioning to a nearby viewing portal.

Tourists down below.

Langdon and Sienna moved to the portal and peered out, seeing that they were currently perched above the Ponte Vecchio—the medieval stone bridge that serves as a pedestrian walkway into the old city. Below them, the day’s first tourists were enjoying the market that has been held on the bridge since the 1400s. Today the vendors are mostly goldsmiths and jewelers, but that has not always been the case. Originally, the bridge had been home to Florence’s vast, open-air meat market, but the butchers were banished in 1593 after the rancid odor of spoiled meat had wafted up into the Vasari Corridor and assaulted the delicate nostrils of the grand duke.

Down there on the bridge somewhere, Langdon recalled, was the precise spot where one of Florence’s most infamous crimes had been committed. In 1216, a young nobleman named Buondelmonte had rejected his family’s arranged marriage for the sake of his true love, and for that decision he was brutally killed on this very bridge.

His death, long considered “Florence’s bloodiest murder,” was so named because it had triggered a rift between two powerful political factions—the Guelphs and Ghibellines—who had then waged war ruthlessly for centuries against each other. Because the ensuing political feud had brought about Dante’s exile from Florence, the poet had bitterly immortalized the event in his Divine Comedy: O Buondelmonte, through another’s counsel, you fled your wedding pledge, and brought such evil!

To this day, three separate plaques—each quoting a different line from Canto 16 of Dante’s Paradiso—could be found near the murder site. One of them was situated at the mouth of the Ponte Vecchio and ominously declared:

BUT FLORENCE, IN HER FINAL PEACE, WAS FATED TO OFFER UP UNTO THAT MUTILATED STONE GUARDIAN UPON HER BRIDGE … A VICTIM.

Langdon raised his eyes now from the bridge to the murky waters it spanned. Off to the east, the lone spire of the Palazzo Vecchio beckoned.

Even though Langdon and Sienna were only halfway across the Arno River, he had no doubt they had long since passed the point of no return.

Thirty feet below, on the cobblestones of the Ponte Vecchio, Vayentha anxiously scanned the oncoming crowd, never imagining that her only redemption had, just moments before, passed directly overhead.

CHAPTER 33

Deep in the bowels of the anchored vessel The Mendacium, facilitator Knowlton sat alone in his cubicle and tried in vain to focus on his work. Filled with trepidation, he had gone back to viewing the video and, for the past hour, had been analyzing the nine-minute soliloquy that hovered somewhere between genius and madness.