The rain was falling in sheets as Dr. Elizabeth Sinskey burst out of Hagia Sophia with Langdon, Brüder, and their bewildered guide, Mirsat.
Follow deep into the sunken palace, Sinskey thought.
The site of the city's cistern-Yerebatan Sarayi-was apparently back toward the Blue Mosque and a bit to the north.
Mirsat led the way.
Sinskey had seen no other option but to tell Mirsat who they were and that they were racing to thwart a possible health crisis within the sunken palace.
"This way!" Mirsat called, leading them across the darkened park. The mountain of Hagia Sophia was behind them now, and the fairy-tale spires of the Blue Mosque glistened ahead.
Hurrying beside Sinskey, Agent Brüder was shouting into his phone, updating the SRS team and ordering them to rendezvous at the cistern's entrance. "It sounds like Zobrist is targeting the city's water supply," Brüder said, breathless. "I'm going to need schematics of all conduits in and out of the cistern. We'll run full isolation and containment protocols. We'll need physical and chemical barriers along with vacuum-"
"Wait," Mirsat called over to him. "You misunderstood me. The cistern is not the city water supply. Not anymore!"
Brüder lowered his phone, glaring at their guide. "What?"
"In ancient times, the cistern held the water supply," Mirsat clarified. "But no longer. We modernized."
Brüder came to a stop under a sheltering tree, and everyone halted with him.
"Mirsat," Sinskey said, "you're sure that nobody drinks the water out of the cistern?"
"Heavens no," Mirsat said. "The water pretty much just sits there ... eventually filtering down into the earth."
Sinskey, Langdon, and Brüder all exchanged uncertain looks. Sinskey didn't know whether to feel relieved or alarmed. If nobody comes in regular contact with the water, why would Zobrist choose to contaminate it?
"When we modernized our water supply decades ago," Mirsat explained, "the cistern fell out of use and became just a big pond in an underground room." He shrugged. "These days it's nothing more than a tourist attraction."
Sinskey spun toward Mirsat. A tourist attraction? "Hold on ... people can go down there? Into the cistern?"
"Of course," he said. "Many thousands visit every day. The cavern is quite striking. There are boardwalks over the water ... and even a small café. There's limited ventilation, so the air is quite stuffy and humid, but it's still very popular."
Sinskey's eyes locked on Brüder, and she could tell that she and the trained SRS agent were picturing the same thing-a dark, humid cavern filled with stagnant water in which a pathogen was incubating. Completing the nightmare was the presence of boardwalks over which tourists moved all day long, just above the water's surface.
"He created a bioaerosol," Brüder declared.
Sinskey nodded, slumping.
"Meaning?" Langdon demanded.
"Meaning," Brüder replied, "that it can go airborne."
Langdon fell silent, and Sinskey could see that he was now grasping the potential magnitude of this crisis.
An airborne pathogen had been on Sinskey's mind as a possible scenario for some time, and yet when she believed that the cistern was the city's water supply, she had hoped maybe this meant that Zobrist had chosen a water-bound bioform. Water-dwelling bacteria were robust and weather-resistant, but they were also slow to propagate.
Airborne pathogens spread fast.
"If it's airborne," Brüder said, "it's probably viral."
A virus, Sinskey agreed. The fastest-spreading pathogen Zobrist could choose.
Releasing an airborne virus underwater was admittedly unusual, and yet there were many life-forms that incubated in liquid and then hatched into the air-mosquitoes, mold spores, the bacterium that caused Legionnaires' disease, mycotoxins, red tide, even human beings. Sinskey grimly pictured the virus permeating the cistern's lagoon ... and then the infected microdroplets rising into the damp air.
Mirsat was now staring across a traffic-jammed street with a look of apprehension on his face. Sinskey followed his gaze to a squat, red-and-white brick building whose single door was open, revealing what looked to be a stairwell. A scattering of well-dressed people seemed to be waiting outside under umbrellas while a doorman controlled the flow of guests who were descending the stairs.
Some kind of underground dance club?
Sinskey saw the gold lettering on the building and felt a sudden tightness in her chest. Unless this club was called the Cistern and had been built in A.D. 523, she realized why Mirsat was looking so concerned.
"The sunken palace," Mirsat stammered. "It seems ... there is a concert tonight."
Sinskey was incredulous. "A concert in a cistern?!"
"It's a large indoor space," he replied. "It is often used as a cultural center."
Brüder had apparently heard enough. He dashed toward the building, sidestepping his way through snarled traffic on Alemdar Avenue. Sinskey and the others broke into a run as well, close on the agent's heels.
When they arrived at the cistern entrance, the doorway was blocked by a handful of concertgoers who were waiting to be let in-a trio of women in burkas, a pair of tourists holding hands, a man in a tuxedo. They were all clustered together in the doorway, trying to keep out of the rain.
Sinskey could hear the melodic strains of a classical music composition lilting up from below. Berlioz, she guessed from the idiosyncratic orchestration, but whatever it was, it felt out of place here in the streets of Istanbul.
As they drew closer to the doorway, she felt a warm wind rushing up the stairs, billowing from deep inside the earth and escaping from the enclosed cavern. The wind brought to the surface not only the sound of violins, but the unmistakable scents of humidity and masses of people
It also brought to Sinskey a deep sense of foreboding.
As a group of tourists emerged from the stairs, chatting happily as they exited the building, the doorman allowed the next group to descend.
Brüder immediately moved to enter, but the doorman stopped him with a pleasant wave. "One moment, sir. The cistern is at capacity. It should be less than a minute until another visitor exits. Thank you."
Brüder looked ready to force his way in, but Sinskey placed a hand on his shoulder and pulled him off to one side.
"Wait," she commanded. "Your team is on the way and you can't search this place alone." She motioned to the plaque on the wall beside the door. "The cistern is enormous."
The informational plaque described a cathedral-size subterranean room-nearly two football fields in length-with a ceiling spanning more than a hundred thousand square feet and supported by a forest of 336 marble columns.
"Look at this," Langdon said, standing a few yards away. "You're not going to believe it."
Sinskey turned. Langdon motioned to a concert poster on the wall.
Oh, dear God.
The WHO director had been correct in identifying the style of the music as Romantic, but the piece that was being performed had not been composed by Berlioz. It was by a different Romantic composer-Franz Liszt.
Tonight, deep within the earth, the Istanbul State Symphony Orchestra was performing one of Franz Liszt's most famous works-the Dante Symphony-an entire composition inspired by Dante's descent into and return from hell.
"It's being performed here for a week," Langdon said, scrutinizing the poster's fine print. "A free concert. Underwritten by an anonymous donor."
Sinskey suspected that she could guess the identity of the anonymous donor. Bertrand Zobrist's flair for the dramatic, it seemed, was also a ruthless practical strategy. This week of free concerts would lure thousands more tourists than usual down into the cistern and place them in a congested area ... where they would breathe the contaminated air, then travel back to their homes both here and abroad.
"Sir?" the doorman called to Brüder. "We have room for a couple more."
Brüder turned to Sinskey. "Call the local authorities. Whatever we find down there, we'll need support. When my team arrives, have them radio me for an update. I'll go down and see if I can get a sense of where Zobrist might have tethered this thing."
"Without a respirator?" Sinskey asked. "You don't know for a fact the Solublon bag is intact."
Brüder frowned, holding his hand up in the warm wind that was blowing out of the doorway. "I hate to say this, but if this contagion is out, I'm guessing everyone in this city is probably infected."
Sinskey had been thinking the same thing but hadn't wanted to say it in front of Langdon and Mirsat.
"Besides," Brüder added, "I've seen what happens to crowds when my team marches in wearing hazmat suits. We'd have full-scale panic and a stampede."
Sinskey decided to defer to Brüder; he was, after all, the specialist and had been in situations like this before.
"Our only realistic option," Brüder told her, "is to assume it's still safe down there, and make a play to contain this."
"Okay," Sinskey said. "Do it."
"There's another problem," Langdon interjected. "What about Sienna?"
"What about her?" Brüder demanded.
"Whatever her intentions may be here in Istanbul, she's very good with languages and possibly speaks some Turkish."
"Sienna knows the poem references the 'sunken palace,' " Langdon said. "And in Turkish, 'sunken palace' literally points ..." He motioned to the "Yerebatan Sarayi" sign over the doorway. "... here."
"That's true," Sinskey agreed wearily. "She may have figured this out and bypassed Hagia Sophia altogether."
Brüder glanced at the lone doorway and cursed under his breath. "Okay, if she's down there and plans to break the Solublon bag before we can contain it, at least she hasn't been there long. It's a huge area, and she probably has no idea where to look. And with all those people around, she probably can't just dive into the water unnoticed."
"Sir?" the doorman called again to Brüder. "Would you like to enter now?"
Brüder could see another group of concertgoers approaching from across the street, and nodded to the doorman that he was indeed coming.
"I'm coming with you," Langdon said, following.
Brüder turned and faced him. "No chance."
Langdon's tone was unyielding. "Agent Brüder, one of the reasons we're in this situation is that Sienna Brooks has been playing me all day. And as you said, we may all be infected already. I'm helping you whether you like it or not."
Brüder stared at him a moment and then relented.
As Langdon passed through the doorway and began descending the steep staircase behind Brüder, he could feel the warm wind rushing past them from the bowels of the cistern. The humid breeze carried on it the strains of Liszt's Dante Symphony as well as a familiar, yet ineffable scent ... that of a massive crush of people congregated together in an enclosed space.
Langdon suddenly felt a ghostly pall envelop him, as if the long fingers of an unseen hand were reaching out of the earth and raking his flesh.
The symphony chorus-a hundred voices strong-was now singing a well-known passage, articulating every syllable of Dante's gloomy text.
"Lasciate ogne speranza," they were now chanting, "voi ch'entrate."
These six words-the most famous line in all of Dante's Inferno-welled up from the bottom of the stairs like the ominous stench of death.
Accompanied by a swell of trumpets and horns, the choir intoned the warning again. "Lasciate ogne speranza voi ch'entrate!"
Abandon all hope, ye who enter here!