Sandy shook her head. “They’re leaving, so they can bomb the whole city and wipe us out.”

“They wouldn’t do that,” said Kira, and got ready to explain about Delarosa and the bomb, but then decided against it. As long as everyone is scared enough to leave, Kira thought. “But Haru’s right, we are all in danger. What about you? Why haven’t you left?”

“There are still injured people in the city,” said Sandy. “Someone has to stay behind to take care of them. Nurse Hardy is here, too.”

“And Skousen?” asked Marcus.

Sandy shook her head. “The Partials took him weeks ago, when the bioweapon first surfaced.” She noticed the confusion on their faces and frowned. “You haven’t heard? There’s a plague that kills Partials—their own version of RM. I guess someone’s finally giving them a taste of their own . . . nonmedicine. That’s the other reason their army left town; nobody wanted to stay here after Partials started falling ill.”

Kira wondered how Skousen or anyone else could have engineered a Partial plague so quickly, but that was the least of her worries. Wherever the plague came from, it was one more obstacle that would convince the Partials and humans they could never dare to trust one another. She clenched her fist, as if she was trying to hold on to her hope like a tangible object. “You need to get out now,” said Kira. “It was very brave of you to stay behind, but it’s time to leave; the Partials will be leaving too, so there won’t be any new patients to deal with. Get everyone dressed, gather all the food and medicine you can, and get out.”

Sandy shook her head. “Two of our patients can’t even walk.”

“Then we’ll pull them in rickshaws,” said Kira. “I’ll pull one myself. The threat is real, and we don’t have long—just go.”

Sandy hesitated a moment, then nodded and ran down the hall. She only got a few steps before a deep rumbling sound rippled through the air; Kira felt it first in her gut, shaking her ribs, then throbbing in her ears like a low, steady beat. She looked at Sandy, who looked back and shook her head; she didn’t know what it was either.

“It’s a rotor,” said Marcus. “A flying vehicle, like an airplane with vertical takeoff. We saw them in White Plains.” He looked at Sandy. “You didn’t recognize the noise?”

“We’ve never seen anything fly before,” said Sandy. “This is new.”

The door to the stairwell flew open and Nurse Hardy burst out in a frenzy, wheezing for breath and gripping the door frame for support. “They’re on the roof,” she gasped. “They’ve come for the patients. Is that . . . Kira Walker?”