Vanderslice’s eyes flickered with fear.

“Don’t worry. I’m not going to drink yours—unless you want me to take it all, so that I can give you back some of mine in exchange.” Marcus was determined to do a better job of explaining what was about to happen to Vanderslice than Matthew had done with him, and drew on what Gallowglass had told him on board the Aréthuse. “Humans aren’t the only creatures in the world, you see. There are vampires, like me, who drink blood. There are also witches, who wield unspeakable power. They can die, though, just like humans. So can daemons. They’re really clever. I thought you might be a daemon, but you don’t smell like one.”

Marat had smelled like fresh air and electricity, as if one of Dr. Franklin’s experiments had come to life.

“Daemon?” Vanderslice’s voice was faint.

“I like daemons,” Marcus said fondly, still thinking of Marat. “You would, too. Never a dull moment when there are daemons around. Vampires can be a bit unimaginative.”

Vanderslice wiped the back of his hand across his mouth. It came away black and bloodied. He examined it for a moment, then shrugged.

“What have I got to lose?” Vanderslice said.

“Not much,” Marcus admitted. “You’re going to die either way. The only difference is that if I take your life before the fever does, you can drink my blood and probably survive. No guarantees, though. I’ve never done this before.”

“That’s what you said to Cuthbert when you cut that wire out of his thumb,” Vanderslice said. “He did all right, as I remember.”

“If you come out of this alive, you’ll have to tell me all about Cuthbert, and Adam’s last days, and even Captain Moulder,” Marcus said. “Deal?”

“Deal,” Vanderslice replied with a hint of his old grin. “But only if you return the favor and tell me stories of France.”

“I met Franklin, you know,” Marcus said.

“No!” Vanderslice began to wheeze again. This time, the laughter turned to coughing, the coughing to vomiting, and the vomit was blackly red.

“You sure, Claes?” Marcus had never called Vanderslice by his given name, but this seemed like the moment to do it.

“Why not,” Vanderslice replied.

“I’ve got to bite you first, to take your blood,” Marcus explained, just as he had once explained inoculation to the soldiers at Trenton. “Then I’ll drink every drop of it.”

“Won’t you get sick with the yellow fever if you do?” Vanderslice asked.

Marcus shook his head. “No. Vampires don’t get sick.”

“Sounds good to me,” Vanderslice said wearily.

“You might get scared when I bite you, but try not to fight me. It will be over before you know it,” Marcus said, using his best bedside manner. “Then I’ll ask you to take my blood. Drink as much of it as you can. You’ll see things—all sorts of things. Betsy and Gallowglass, my voyage here on the ship, the chevalier de Clermont. Don’t let that stop you. Just keep drinking.”

“Any pretty girls?” Vanderslice said.

“A few,” Marcus said. “But one of the prettiest is your great-grandmother, so no lewd thoughts.”

Vanderslice crossed his heart with trembling fingers. “Then what happens?”

“Then we figure out how we’re going to survive in a city full of dead people until it’s safe to move you somewhere else.” Marcus figured there was no point in being anything less than honest. “You ready?”

Vanderslice nodded.

Marcus took his friend into his arms. He held him close, like a lover. Like a child. He hesitated. What if Gallowglass was right? What if he regretted this?

Vanderslice looked up at him, quiet and trusting.

Marcus bit into his friend’s neck. He tasted sour and dirty, bitter with fever and the sickly taste of imminent death. It was all Marcus could do to continue, to keep drawing Vanderslice’s blood into his mouth and then swallow it down.

He kept going, though. He owed Vanderslice that.

When there was nothing more to take, and Vanderslice’s veins were dry and his heart on the verge of stopping, Marcus bit into his own wrist and held it up to Vanderslice’s mouth.

“Drink.” Marcus’s voice had the same note of calm concern that it did when he was seeing a patient, or working on a hospital ward. Trust me, was the unspoken message.

Vanderslice did. He latched on with teeth and tongue, instinctively thirsty for what would bring him back to life.

Marcus had to stop Vanderslice—his son, he reminded himself—before he passed out from loss of blood. He couldn’t take care of an infant if he were out cold. Gently, he drew away. Vanderslice snarled at him.

“You can have more,” Marcus told him. “Just let that settle for a moment.”

Vanderslice covered his ears. “Why are you shouting?” he whispered.

“I’m not. Your senses are sharper, that’s all,” Marcus explained.

“I’m thirsty,” Vanderslice complained.

“You will be. For weeks,” Marcus said. “Tired, too. But you won’t be able to sleep. I didn’t sleep for nearly two years after Matthew made me a vampire. Lie back and close your eyes. It’s best if you don’t try to do too much too fast.”

That was one of the things that Marcus learned when he and Matthew had run from Yorktown to Pennsylvania to New York to Massachusetts. He was glad he got to share his hard-won knowledge with someone, instead of being the one always asking questions from older, more experienced vampires. So far, Marcus liked being a father.

“While you rest, I’ll tell you about France. About your new family.” Marcus felt a bit delirious himself, after all the exertion. He closed his eyes, too, pleased that it had all gone so well.

* * *

—

“I TOLD YOU not to do it,” Gallowglass said, hauling Vanderslice out of the water.

“I had to. He deserved a second chance,” Marcus said. “It was my duty—”

“No. Saving the world is not your duty. I know that’s what Matthew tries to do, but it’s going to get us all killed one day.” Gallowglass shook the water off Vanderslice. “Your duty is to listen to Philippe and do precisely what he tells you and nothing more. You are supposed to be in Hertfordshire, counting sheep. Instead, you’re in Philadelphia making babies.”

“I’m not a baby,” Vanderslice snarled, snapping his teeth at Gallowglass.

“Have you ever seen a toothless vampire?” Gallowglass asked Vanderslice.

“No,” he replied.

“There’s a reason for that,” Gallowglass growled. “Try to bite me again and you’ll learn what it is.”

“Why is he so . . .” Marcus waved his hands in the air, unable to put Vanderslice’s behavior into words. Being an infant wasn’t easy, but Vanderslice was behaving like a lunatic, running after dogs in the street and stealing meat from the butchers in the market house. If he wasn’t more careful, he’d get himself killed or, even worse, arrested.

“Because you’re too young to be a father, Marcus. I told you as much,” Gallowglass said. “There are good reasons why Philippe forbade you from siring children.”

“What are they?” Marcus demanded.

“I can’t tell you.” Gallowglass dropped Vanderslice on the slimy cobblestones of Front Street. They were coated with bits of rotten fish, seaweed, and manure. “You need to ask Matthew.”

“Matthew isn’t here!” Marcus shouted, at the end of his tether.

“And you can thank your lucky stars for that, lad,” Gallowglass said. “Take my advice. Dry out young Claes and leave Philadelphia. He’s known here. You may be, too. Go to New York. That’s a city that will swallow you both up whole, and nobody will notice.”

“What do I do in New York?” Marcus said.

Gallowglass looked at him with pity.

“Whatever you fancy,” his cousin said. “And you better enjoy it, because it will be the last taste of independence you get after Matthew and Philippe find out what you’ve done.”