“Nathaniel, where did all those vampires come from in the first place?” I said. “I can’t believe we never thought about this before.”

Nathaniel frowned. “I presumed that Therion and Azazel gathered vampires from other regions to them. The courts in Chicago were certainly not that big.”

“But where was Therion keeping them all?” I asked, remembering the vampires that had poured into Daley Plaza. “They had to have somewhere to gather.”

“They seemed to be coming from the underground,” Nathaniel said.

I nodded. “There could be thousands more down there, in the pedways and the freight tunnels.”

“If any of them have taken the serum, then you should still be able to call them to you,” Nathaniel said.

“What if not all of them have taken it?” I asked.

“As you say, let us worry about it at another time,” he said. “The majority of the vampires that we saw were strolling under the sun, and you know that you can reach them. Once we have wiped out the majority, then we can deal with the stragglers of this infestation.”

“Okay,” I said, trying not to worry. “Okay.”

We approached the museum campus and Soldier Field from the north, almost perfectly retracing the path we had walked just a few days before. The surface of Lake Michigan was covered in Alerian’s fog for as far as the eye could see. Beneath the fog there were dark shadows moving.

“No one is ever going to come back to this city,” I said, my heart breaking a little. “And if anyone does, they’ll never truly feel safe here again.”

Nathaniel followed my gaze, saw the shadows shifting. “You do not know that Alerian intends harm to the people of the city,” he said, but he didn’t sound very certain.

“He doesn’t have to intend harm in order for people to get caught in the cross fire,” I said.

We flew over the top of the large bowl that perched on top of the original structure of Soldier Field. I lowered down to the center of the field, right on the fifty-yard line.

“I don’t know what’s going to happen when I try to do this,” I warned Nathaniel. “You might want to be ready to run.”

He looked insulted. “I would not leave you any more than you would leave me. Shall I help you? I can boost your power, as we did before.”

“I don’t think that’s a good idea,” I said. We’d end up naked and rolling in the grass instead of wiping out the vampires. “Just make sure nothing attacks me while I try to draw the vamps here, okay?”

Nathaniel nodded. “Very well.”

I closed my eyes and drew deep within myself, searching for the spark of magic that came from Azazel. It was buried deep. I hadn’t acknowledged my relationship with Azazel for some time, but blood didn’t lie. He was inside me, whether I wanted him to be there or not.

When I found the source of Azazel’s power I drew it forth so that it was at the forefront of my magic. Underneath that stream I layered my Agent’s strength. Finally, I took both abilities, wound them together, and used the power of the Morningstar to push the call forth. The call of blood. It poured out of me, seeking blood that had the same qualities as mine.

My magic quested all over the city, long tentacles brushing up against living things in search of what it wanted. I felt the presence of other creatures, other things that lay in wait should the vampires fail. Some of those creatures felt me, too, and the wise ones fled.

I would take care of the stupid ones later.

My power touched the humans that remained in Chicago, whether imprisoned by Therion or hiding in their own warrens, little rabbits trembling with fear as they felt me pass by.

The Agents hunched over their desks or collecting souls paused. They felt something, but they couldn’t figure out what. The call of the Agent’s blood had tugged on them for a moment, but since they didn’t also possess the blood of Azazel, it passed them by.

Only two looked up and knew it was me, and they stood facing each other across a desk.

“Maddy?” J.B. said, looking into thin air.

“Black,” Sokolov growled.

I kept going until I found a vampire that had been infected by the serum. I lit the fire of compulsion inside it, and then I found that I did not have to draw each vampire to me individually. Azazel had made the formula so that when one was compelled, all would have to follow. I pulled them toward me, made it impossible for them to resist.

I could feel them in my head, all of them, thousands upon thousands of vampires. They emerged from buildings and sewers. They abandoned their posts at the human encampment, released victims they had been in the midst of torturing. They surged toward me, like a great, black wave.

There was one I searched for among the many, one that I did not feel.

Therion. He was smart enough to have realized that any gift from a fallen angel came with a price. He hadn’t taken the serum.

A moment later, I did feel his presence. But not the way I thought I would.

Therion’s power snaked along the mindless rows of marching vampires, making them pause, making them turn back to their master.

“No,” I said, and drew them toward me again, pushing more power into my spell.

Therion tugged back, trying to re-exert his influence over the horde. I sensed some of them waking up from my compulsion, turning back to him.

“No,” I snarled, and this time I really put some force into it. I sent a pulse of magic through the original spell, and shot it inside Therion’s.