The corridor split into two branches—one that led back to the stairs and the first floor, and one that probably led deeper into the basement. My decision to play Nancy Drew already made, I took the road not yet traveled.

I moved slowly, one shoulder nearly against the wall, trying to make myself as invisible as possible. The hallway dead-ended in a T-shaped corridor; I headed for it. This part of the basement was well lit, so I kept the flashlight off, but gripped it with such force, my palm was actually sweating. I was still in the basement, still close to whatever nasties Scout had locked behind the big metal door. That meant I needed to be on my guard.

I made it to the dead end without incident, then glanced down the left- and right-hand corridors. Both were empty, and I had no clue where I was relative to the rest of the building. Worse, both hallways were long and dark. There were no overhead lights and no wall sconces—just darkness.

Not the best of choices. I didn’t have a coin to flip or a Magic 8-Ball to ask, so I went with the only other respectable method of making a decision as important at this one.

Unfortunately, I’d only made it through “eeny meeny miney mo” when the ground began to rumble beneath my feet. I was thrown forward into the crux of the hallway, and had to brace myself against the limestone wall to stay upright as the floor vibrated beneath me.

But just as suddenly as it had begun, the rumbling stopped. My palm still flat against the limestone bricks, heart pounding in my chest, I looked up at the ceiling above me as I waited for screaming and footfalls and other telltale signs of the aftermath of the Earthquake That Ate Chicago.

There was only silence.

I snapped my gaze to the left as hurried footsteps echoed toward me from that end of the hallway and tried to swallow down the panic.

I flicked on my flashlight and swung the beam into the dark, the arc of light barely penetrating the blackness, even as I squinted to get a better look.

And then I saw them—Scout and Jason behind her, both in uniform, both running toward me as if they were running for their lives. I dropped the beam of the flashlight to the floor to keep from blinding them, afraid that’s exactly what was happening.

“Scout?” I called out, but fear had frozen my throat. I tried again, and this time managed some sound. “Scout!”

They were still far away—the corridor was a deep one—but they were running at sprinter speed . . . and there was something behind them.

It almost didn’t surprise me to see that they were being chased. After all, I’d already helped Scout try to escape from something. But I’m not sure what I expected to see chasing her.

As they drew closer, I realized that behind them was the blonde we’d seen outside the pillar garden on Monday—the girl with the hoodie who had watched us from the street. She ran full-bore behind Scout and Jason. But even as she sprinted through the corridor, her expression was somehow vacant, a strange gleam in her eyes the only real sign of life. Her hair was long and wavy, and it flew out behind her as she ran, arms pumping, toward us.

Suddenly she pulled back her hand, then shot if forward, as if to throw something at the two of them. The air and ground rumbled, and this time, the rumble was strong enough to knock me off my feet. I hit the ground on my knees, palms extended.

By the time I glanced up again, Scout and Jason were only feet in front of me. That meant the blond girl was only a few yards behind. I saw the look of horror on Scout’s face. “Get up, Lily!” she implored. “Run!”

I muttered a curse that would have made a string of sailors blush, and ignoring the bruises blossoming on my knees, jumped to my feet and did as I was ordered. The three of us took off down the hallway, presumably for a safer place.

We ran through one corridor, then another, then another, heading in the opposite direction of the path I’d taken with the brat pack—probably a good thing, since there was no giant metal door in that part of the convent to keep them out.

To keep her out.

Whatever juju the blonde used before, she used again, the ground rumbling beneath our feet. I don’t know how she managed it, how she managed to make the earth—and all the limestone above it—move, but she did it sure enough. We all stumbled, but Scout reached out a hand and grabbed at the wall to keep her balance, and Jason caught Scout’s elbow. I caught limestone, the stones rushing toward my face as she knocked me off my feet again. I braced myself on my hands, the pads of my hands burning as I hit the floor.

They were on their feet again and yards ahead before they realized I wasn’t with them.

“Lily!” Scout screamed, but I was already looking behind me, watching the blonde. The earthquake- maker just stood there, and I figured if I was already on the floor, there wasn’t much else she could do to me.

Of course, that didn’t mean the guy who stepped out from behind her couldn’t do damage. He was older than she was—college, maybe. Curly dark hair, broad shoulders, and blue eyes that gleamed with a creepy intensity. With a hunger. And all that hunger and intensity was directed at me.

I swallowed down fear and panic and tried to make my brain work, tried to make my arms and legs push me up from the floor, but I was suddenly puppy-clumsy, unable to order my limbs to function.

The boy stepped beside the blonde, muttered something, and just as she had done, whipped his hand in my direction.

The air pressure in the room changed, and something flew my way, some thing he’d created with that flick of his hand. It looked like a contact lens of hazy, green smoke, but it wasn’t really smoke. It wasn’t really a thing. It was more like the very air in the room had warped.