the lagoon that reflects no stars.
When Langdon stood and stepped back over the stanchions, Mirsat was glaring up at him with a look of alarm and betrayal on his face. Langdon stood almost a foot taller than the Turkish guide.
“Mirsat,” Langdon began. “I’m sorry. As you can see, this is a very unusual situation. I don’t have time to explain, but I have a very important question to ask you about this building.”
Mirsat managed a weak nod. “Okay.”
“Here at Dandolo’s tomb, we can hear a rivulet of water flowing somewhere under the stone. We need to know where this water flows.”
Mirsat shook his head. “I don’t understand. Water can be heard beneath the floors everywhere in Hagia Sophia.”
Everyone stiffened.
“Yes,” Mirsat told them, “especially when it rains. Hagia Sophia has approximately one hundred thousand square feet of rooftops that need to drain, and it often takes days. And usually it rains again before the drainage is complete. The sounds of trickling water are quite common here. Perhaps you are aware that Hagia Sofia sits on vast caverns of water. There was a documentary even, which—”
“Yes, yes,” Langdon said, “but do you know if the water that is audible here at Dandolo’s tomb flows somewhere specific?”
“Of course,” Mirsat said. “It flows to the same place that all the water shedding from Hagia Sophia flows. To the city cistern.”
“No,” Brüder declared, stepping back over the stanchion. “We’re not looking for a cistern. We’re looking for a large, underground space, perhaps with columns?”
“Yes,” Mirsat said. “The city’s ancient cistern is precisely that—a large underground space with columns. Quite impressive actually. It was built in the sixth century to house the city’s water supply. Nowadays it contains only about four feet of water, but—”
“Where is it!” Brüder demanded, his voice echoing across the empty hall.
“The … cistern?” Mirsat asked, looking frightened. “It’s a block away, just east of this building.” He pointed outside. “It’s called Yerebatan Sarayi.”
Sarayi? Langdon wondered. As in Topkapi Sarayi? Signage for the Topkapi Palace had been ubiquitous as they were driving in. “But … doesn’t sarayi mean ‘palace’?”
Mirsat nodded. “Yes. The name of our ancient cistern is Yerebatan Sarayi. It means—the sunken palace.”
CHAPTER 90
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