I jogged over to the directory by the elevator, passing a big window looking out at the square. A dozen or so Hosts encircled the smashed ambulance, a pride of lions zeroing in on their wounded prey. Even from here I could make out the quick puffs of air as they breathed.

I ran my finger down the directory, stopping at RESPIRATORY CARE—FLOOR TWO. I felt my stomach sink.

“We have to go upstairs,” I said.

“Then let’s go.” Patrick hoisted the tank in one hand and followed me to the wide stairs, being careful not to let the tube tug the mask away from his face. Any snag in the line could mean death.

We took each corner slowly, pausing at the landing. I risked a glance at Patrick’s tank—the dial even further in the red.

He shook his head again hard, as if trying to jar something loose inside it. In the distance I could hear the siren wailing away. I wondered how long it would hold the Hosts’ attention.

When we stepped out onto the second floor, it looked dark and still. Blue and red flickered in the window at the corridor’s end, the ambulance’s lights still flashing through the darkness. An overhead sign directed us down a corridor. Side by side, we eased past one doorway, then another.

The squeak of a wheel broke the silence.

We froze.

A crash cart rolled slowly out from one of the patient rooms.

It stopped in the middle of the corridor.

We stared at it there, about ten feet away, blocking our path. Patrick’s breath fogged the mask quicker and quicker, burning oxygen.

From deep in the room came the tick-tock of shoes against the floor. Then that awful shallow panting.

A Host dressed in ripped nurse’s scrubs emerged calmly, her gaze forward, her head twitching. Psychiatric restraints—thick leather cuffs lined with padding—swung from her drawstring. Seemingly she hadn’t heard us; she’d just bumped the cart as she’d moved around in the room. She wore clogs with slim heels that flexed her calves. From the side she looked almost normal.

When Patrick set the portable tank down, it gave the faintest clank.

Her head pivoted to face us.

I didn’t recognize her. Much of the hospital staff came in from Lawrenceville or Stark Peak for two-day shifts. Fluffy blond hair floated around her defined cheekbones. In another life she might have been attractive. But the holes bored through her eyes caught the shadows, giving her face a skull-like appearance in the low light.

Patrick raised the shotgun.

“Wait,” I said. “The noise’ll draw the—”