Before Langdon could continue, the loud clunk of a dead bolt echoed across the baptistry. The tourist entrance had apparently just been unlocked from outside.

“Grazie mille,” said the man with the rash on his face. A thousand thanks.

The baptistry docent nodded nervously as he pocketed the five hundred dollars cash and glanced around to make sure nobody was watching.

“Cinque minuti,” the docent reminded, discreetly swinging open the unbolted door just wide enough for the man with the rash to slip inside. The docent closed the door, sealing the man inside and blocking out all sound from outside. Five minutes.

Initially the docent had refused to take pity on the man who claimed to have come all the way from America to pray at the Baptistry of San Giovanni in hopes of curing his terrible skin disease. Eventually, though, he had been inspired to become sympathetic, aided no doubt by an offer of five hundred dollars for five minutes alone in the baptistry … combined with the growing fear that this contagious-looking person would stand there beside him for the next three hours until the building opened.

Now, as he moved stealthily into the octagonal sanctuary, the man felt his eyes drawn reflexively upward. Holy shit. The ceiling was like nothing he’d ever seen. A three-headed demon stared down directly at him, and he quickly lowered his gaze to the floor.

The space appeared to be deserted.

Where the hell are they?

As the man scanned the room, his eyes fell on the main altar. It was a massive rectangular block of marble, set back in a niche, behind a barrier of stanchions and swags to keep spectators away.

The altar appeared to be the only hiding place in the entire room. Moreover, one of the swags was swinging slightly … as if it had just been disturbed.

Behind the altar, Langdon and Sienna crouched in silence. They had barely had time to collect the dirty towels and straighten the font cover before diving out of sight behind the main altar, with the death mask carefully in tow. The plan was to hide here until the room filled up with tourists, and then discreetly exit among the crowd.

The baptistry’s north door had definitely just been opened — at least for a moment — because Langdon had heard sounds emanating from the piazza, but then just as abruptly, the door had been closed, and all had gone quiet again.

Now, back in the silence, Langdon heard a single set of footsteps moving across the stone floor.

A docent? Checking the room before opening it to tourists later today?

He had not had time to extinguish the spotlight over the baptismal font and wondered if the docent would notice. Apparently not. The footsteps were moving briskly in their direction, pausing just in front of the altar at the swag that Langdon and Sienna had just vaulted over.

There was a long silence.

“Robert, it’s me,” a man’s voice said angrily. “I know you’re back there. Get the hell out here and explain yourself.”

There’s no point in pretending I’m not here.

Langdon motioned for Sienna to remain crouched safely out of sight, holding the Dante death mask, which he had resealed in the Ziploc bag.

Then, slowly, Langdon rose to his feet. Standing like a priest behind the altar of the baptistry, Langdon gazed out at his congregation of one. The stranger facing him had sandy-brown hair, designer glasses, and a terrible rash on his face and neck. He scratched nervously at his irritated neck, his swollen eyes flashing daggers of confusion and anger.

“You want to tell me what the hell you’re doing, Robert?!” he demanded, stepping over the swag and advancing toward Langdon. His accent was American.

“Sure,” Langdon replied politely. “But first, tell me who you are.”

The man stopped short, looking incredulous. “What did you say?!”

Langdon sensed something vaguely familiar in the man’s eyes … his voice, too, maybe. I’ve met him … somehow, somewhere. Langdon repeated his question calmly. “Please tell me who you are and how I know you.”

The man threw up his hands in disbelief. “Jonathan Ferris? World Health Organization? The guy who flew to Harvard University and picked you up!?”

Langdon tried to process what he was hearing.

“Why haven’t you called in?!” the man demanded, still scratching at his neck and cheeks, which looked red and blistered. “And who the hell is the woman I saw you come in here with?! Is she the one you’re working for now?”

Sienna scrambled to her feet beside Langdon and immediately took charge. “Dr. Ferris? I’m Sienna Brooks. I’m also a doctor. I work here in Florence. Professor Langdon was shot in the head last night. He has retrograde amnesia, and he doesn’t know who you are or what happened to him over the last two days. I’m here because I’m helping him.”

As Sienna’s words echoed through the empty baptistry, the man cocked his head, puzzled, as if her meaning had not quite registered. After a dazed beat, he staggered back a step, steadying himself on one of the stanchions.

“Oh … my God,” he stammered. “That explains everything.”

Langdon watched the anger drain from the man’s face.

“Robert,” the newcomer whispered, “we thought you had …” He shook his head as if trying to get the pieces to fall into place. “We thought you had switched sides … that maybe they had paid you off … or threatened you … We just didn’t know!”

“I’m the only one he’s spoken to,” Sienna said. “All he knows is he woke up last night in my hospital with people trying to kill him. Also, he’s been having terrible visions — dead bodies, plague victims, and some woman with silver hair and a serpent amulet telling him—”

“Elizabeth!” the man blurted. “That’s Dr. Elizabeth Sinskey! Robert, she’s the person who recruited you to help us!”

“Well, if that’s her,” Sienna said, “I hope you know that she’s in trouble. We saw her trapped in the back of a van full of soldiers, and she looked like she’d been drugged or something.”

The man nodded slowly, closing his eyes. His eyelids looked puffy and red.

“What’s wrong with your face?” Sienna demanded.

He opened his eyes. “I’m sorry?”

“Your skin? It looks like you contracted something. Are you ill?”

The man looked taken aback, and while Sienna’s question was certainly blunt to the point of rudeness, Langdon had wondered the same thing. Considering the number of plague references he’d encountered today, the sight of red, blistering skin was unsettling.

“I’m fine,” the man said. “It was the damned hotel soap. I’m deathly allergic to soy, and most of these perfumed Italian soaps are soy-based. Stupid me for not checking.”

Sienna heaved a sigh of relief, her shoulders relaxing now. “Thank God you didn’t eat it. Contact dermatitis beats anaphylactic shock.”

They shared an awkward laugh.

“Tell me,” Sienna ventured, “does the name Bertrand Zobrist mean anything to you?”

The man froze, looking as if he’d just come face-to-face with the three-headed devil.

“We believe we just found a message from him,” Sienna said. “It points to someplace in Venice. Does that make any sense to you?”

The man’s eyes were wild now. “Jesus, yes! Absolutely! Where is it pointing!?”

Sienna drew a breath, clearly prepared to tell this man everything about the spiraling poem she and Langdon had just discovered on the mask, but Langdon instinctively placed a quieting hand on hers. The man certainly appeared to be an ally, but after today’s events, Langdon’s gut told him to trust no one. Moreover, the man’s tie rang a bell, and he sensed he might very well be the same man he had seen praying in the small Dante church earlier. Was he following us?